Logic: Evaluation Project

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MODULE 1:

UNDERSTANDING PHILOSOPHY AND ITS BRANCHES

1 1THE ESSENCE OF PHILOSOPHYPHILOSOPHY DEFINED

PHILOSOPHY & THEOLOGY

ESSENCE OF PHILOSOPHY

BRANCHES OF PHILOSOPHY

1 2UNDERSTANDING SOME PHILOSOPHIESCHRISTIAN PHILOSOPHERS

ST. THOMAS AQUINAS ST. AUGUSTINE

GREEK PHILOSOPHERS

SOCRATES PLATO ARISTOTLE

OTHER PHILOSOPHERS

CONFUCIUS KARL MARX


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1 1 THE ESSENCE OF PHILOSOPHYPHILOSOPHY DEFINED

Reported By: ________________________________________________________________________

PHILOSOPHY- The term is derived from two Greek words,philosand sophiawhich literally mean loverof wisdom.

- The science of beings in their ultimate reasons, causes and principles acquired byhuman reason. (Bittle, 1941)

- The science of things by ultimate principles and causes as known by natural reasonalone. (Pion, 1973)

1. Philosoph y is a science.Science is a systematized body of knowledge based onevidence.

2. Science of things.Philosophy is concerned with everything in the world as far asthe human mind can reach.

3. Ult imate principles and causes.Philosophy explores the ultimate or final cause of

a thing.4. Known only by natura l reason. The philosopher uses his natural reason,

particularly, human reasoning.

PHILOSOPHY & THEOLOGY

There are points in the world that mans rationality cannot fathom. Christianity recognizesmiraclesoccurrences that science cannot explain. Man has no choice but to acknowledge theexistence of God. Man asserts and strengthens his faith in his ascent to find the truth, a truthwhich rationality cannot explain. Man uses philosop hy for rat ional explanation and usestheology for m oral surety.

ESSENCE OF PHILOSOPHYPhilosophy aims to teach man how to have a happy life. This is the essence of phi losoph y.

BRANCHES OF PHILOSOPHY

1. Logicthe formal and systematic study of the principles of valid inference and correctreasoning.

2. Ethics the branch of philosophy dealing with the concepts and principles of morality.3. Epis temology the branch of philosophy dealing with the theory of knowledge its

sources, limits, kinds and reliability.4. Cosmology the scientific study of the universe on the largest scales of space and

time.5. Metaphysicsa traditional branch of philosophy dealing at the most general level with

the nature of existence. The term originated from Aristotles First Philosoph y, themost fundamental and abstract of his writingsta meta ta physikawhich means afterthe physics.

6. Aesthetics / Esthetics the philosophical investigation of art, including all the visualarts, music, literature, drama, and dance.

7. Theodicythe defense and vindication of God, defined as both omnipotent and good inthe light of evil in the world. The term was first used by Gottfried Wilhelm Liebniz in1710.


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1 2 UNDERSTANDING SOME PHILOSOPHIESCHRISTIAN PHILOSOPHERS

ST. THOMAS AQUINAS(1225-1274)

Reported By:_____________________________________

- An Italian philosopher and Theologian of themedieval period, the philosophy of Aquinas hasexerted enormous influence on subsequentChristian theology, especially that of the RomanCatholic Church, but also Western philosophy ingeneral.

- His most important and enduring works areThe "Summa Theolog ica"(Compendium ofTheology) in which he expounds his systematictheology of the Quin quae Viae - The Five Proo fsof the Existence of God, and The "SummaContra Genti les"(On The Trut h Of The CatholicFaith).

He believed that truth becomes known through:

Natural Revelation- certain truths are available to all people through their humannature and through correct human reasoning

Supern atural Revelation- faith-based knowledge revealed through scripture.

He believed that God reveals himself through nature, so that rational thinking and the study ofnature is also the study of God. Aquinas proposed five positive statements about the DivineQualitiesor The Nature of God:

God is s imple, without composition of parts such as body and soul, or matter and form.

God is p erfect, lacking nothing.

God is inf in i te, and not limited in the ways that created beings are physically,intellectually, and emotionally limited.

God is immu table, incapable of change in respect of essence and character.

God is one, such that God's essence is the same as God's existence.

Aquinas believed that the existence of God is neither self-evident nor beyond proof. Inthe "Summa Theologica"he details five rational proofs for the existence of God, the QuinquaeViaeor the Five Ways, some of which are really re-statements of each other:

The argument of the unm oved mo ver (ex m otu): everything that is moved is movedby a mover, therefore there is an unmoved mover from whom all motion proceeds, whichis God.

The argument of the first cause (ex causa): everything that is caused is caused bysomething else; therefore, there must be an uncaused cause of all caused things, whichis God.

The argument from conting ency (ex contingentia): there are contingent beings in theuniverse which may either exist or not exist and, so there must be a necessarybeing who se existence is not contingent on any other being, which is God.
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The argument from degree (ex gradu): there are various degrees of perfection whichmay be found throughout the universe, so there must be a pinnacle of perfect ionfromwhich lesser degrees of perfection derive, which is God.

The te leological argument or argument from design (ex fine): all natural bodies inthe world act towards ends, therefore there must be an intel l igent being that guid es al lnatural bodies towards their ends, which is God.

Aquinas defined the Four Cardinal Virtuesasprudence, temperance,justiceand fortitude,which he held are natural and binding on everyone. In addition, there are Three Theolog icalVirtues, described as faith, hopeand charity, which are supernatural and are distinct from othervirtues in that their object is God.

He distinguished Four Kinds of Laws:

Eternal Law- the decree of God that governs all creation

Natural Law- human "participation" in eternal law, which is discovered by reason

Human Law- the natural law applied by governments to societies

Divine Law- the specially revealed law in the scriptures

For St. Thomas Aquinas, the goal of h uman existence is union and eternal fel lowsh ip with

God. For those who have experienced salvation and redemption through Christ while living onearth, a beatific vision will be granted after death in which a person experiences perfect,unending happiness through comprehending the very essence of God.

ST. AUGUSTINEOF HIPPO (A.D.354 - 430)

Reported By:_____________________________________

- An Algerian-RomanPhilosopher and Theologianof the Late Roman / EarlyMedieval Period. He isone of the most important early figures in thedevelopment of Western Christianity, and was a

major figure in bringing Christianity to dominance inthe previously pagan Roman Empire.

- He is often considered The Father of OrthodoxTheologyand the greatest of The Four GreatFathers of the Latin Church, along with St.

Ambrose,St. Jerome andSt. Gregory.- He is best known for the Confessiones

(Confessions), a personal account of his early life," De Civitate Dei"(The City of God ), consisting of22 books dealing with God, martyrdom, Jews andother Christian philosophies, and De Trinitate(On the Trinity), consisting of 15 books, in which

he developed the "psychological analogy" of theTrinity.

Augustine struggled to reconcile his beliefs about free willand his belief that humansare morally responsible for their actions, with his belief that ones life ispredestined and hisbelief in original sin. He held that, because human beings begin with original sin and aretherefore inherently evil (even if, as he believed, evil is not anything real but merely the absenceof good), then the classical attempts to achieve virtue by discipline, training and reason are
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all bound to fail, and the redemptive action of God's grace alone offers hope. He opined that"We are too weak to discover the truth by reason alone".

GREEK PHILOSOPHERS

SOCRATES(c. 469 - 399 B.C.)

Reported By: __________________________________________________

Socrateswas a hugely important Greek philosopher from the Classicalperiod. Unlike most of thePre-Socratic Philosophers who came beforehim, who were much more interested in establishing how the worldworks, Socrates was more concernedwith how people should behave,and so was perhaps the First Major Philosopher ofEthics. He iscredited as one of the founders ofWestern Philosophy.

The best known part of Socrates' life is histrial and execution. Despite claiming completeloyalty to his city, Socrates' pursuit of virtue and

his strict adherence to truth clashed with thecourse ofAthenian Politics and society. Socratesraised questions aboutAthenian Religion, but alsoaboutAthenian Democracyand, in particular,he praised Athens' arch-rival Sparta, causingsome scholars to interpret his trial as anexpression o f pol i t ical inf ightin g. Whatever themotivation, he was found gui l ty of impiety andcorrupt ing the minds of the youth of Athens,and he was sentenced to death by d rinking amix ture conta in ing poison hemlock in 399 B.C.,at the age of 70.

Socrates himself did not write any philosophical texts, and our knowledge of the man and hisphilosophy is based on writings by his studentsand contemporaries, particularlyPlato'sdialogues, but also the writings ofAristotle,XenophonandAristophanes.

Perhaps Socrates' most important and enduring singlecontribution to Western thought is his dialectical method ofinquiry, which he referred to as "e lenchus"(roughly, "cross-examination") but which has become known as the SocraticMethodor Socratic Debate. It has been called a negativemethod of hypot hesis el imination, in that better hypothesesare found by steadily identifying and eliminatingthose whichlead to contradictions. Its influence is perhaps most stronglyfelt today in the use of the Scienti f ic Method, in which thehypothesis is just the first stage towards a proof.

InPlato's early dialogue, "Apology of Socrates",Socrates refused to pursue conventional politics, on the groundsthat he could not look into the matters of others when he did notyet understand how to live his own.
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Socrates often referred to what the Greeks called a "d aemonic s ign" ,a kind of inner voiceheheard only when he was about to make a mistake. Although we would consider this to beintuition today, Socrates thought of it as a form of "divine madness", the sort of insanity that isa gift from the gods and gives us poetry, mysticism, love and even philosophy itself.

PLATOFATHER OF MODERN PHILOSOPHY

Reported By:______________________________________Plato (c. 427-347 B.C.) came from a family of aristoi,

served in the Peloponnesian War, and was perhaps

Socrates' most famous student. He was twenty-eight

years old when Socrates was put to death. At the age of

forty, Plato established a school at Athens for the

education of Athenian youth. The Academy, as it was

called, remained in existence from 387 B.C. to A.D.529,

when it was closed by Justinian- The Byzantine emperor.Our knowledge of Socrates comes to us from numerousdialogues which Plato wrote after 399. In nearly every

dialogue and there are more than thirty that we knowabout Socrates is the main speaker. The style of thePlato's dialogue is important it is the Socratic style thathe employs throughout. A Socratic Dialogue takes theform of question-answer, question-answer, question-answer.

Socrates taught Plato a great many things, but one of the thingsPlato more or less discovered on his own was that mankind isborn with knowledge. That is, knowledge is present in the humanmind at birth. It is not so much that we "learn" things in our dailyexperience, but that we "recollect" them. This may explain why

Socrates did not give his students answers, but only questions.His job was not to teach truth but to show his students how theycould "pull" truth out of their own minds- it is for this reason thatSocrates often considered himself a midwife in the labor ofknowledge. And this is the point of the dialogues. For only inconversation, only in dialogue, can truth and wisdom come to thesurface.

Plato's greatest and most enduring work was his lengthydialogue,The Republic.This dialogue has often been regardedas Plato's blueprint for a future society of perfection. It discussesa number of topics including the nature of justice, statesmanship,

ethics and the nature of politics. It is in The Republic that Platosuggests that democracy was little more than a "charming form ofgovernment."

The unphilosophical manthat is, all of usis atthe mercy of sense impressions andunfortunately, our sense impressions oftentimesfail us. Our senses deceive us. But because wetrust our senses, we are like prisoners in a cave
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we mistake shadows on a wall for reality. This is the central argument of Plato's ALLEGORYOF THE CAVEwhich appears in Book VII of The Republic.

ARISTOTLE - FATHER OF LOGIC AND SCIENCE

Reported By:____________________________________________

Aristotle (c. 384322 B.C.) was one of the most importantwestern philosophers, a student ofPlato, teacher ofAlexanderThe Great, and tremendously influential in the Middle Ages.

Aristotle wrote on logic, nature,psychology, ethics,politics, andart. He is credited with developing deductive reasoning, theprocedure of logic that fictional detectiveSherlock Holmes usedto solve his cases.

Family of Origin: Aristotle was born in the City of Stagira,Macedonia. His father, Nichomacus, was the personal physicianto King Amyntasof Macedonia.

Aristotle in Athens:In 367, at the age of 17,Aristotle went toAthens to attend theinstitution of philosophical learning known asthe Academy, which was founded by Socrates'pupil Plato, where he stayed until Plato's deathin 347. Then, since he was not namedsuccessor, Aristotle left Athens, travelingaround until 343 when he became tutor for

Amyntas' grandson, Alexander-- later knownas "The Great." In 336, Alexander's father,Philip of Macedonia, was assassinated.

Aristotle returned to Athens in 335.

The Lyceum and Peripatetic Philosophy: Upon hisreturn to Athens, Aristotle lectured for twelve years in aplace that came to be known as the Lyceum. Aristotle'sstyle of lecturing involved walking around in coveredwalkways, for which reason Aristotle was called"Peripatetic" (i.e., walking about).

Aristotle in Exile: In 323, when Alexander the Greatdied, the Assembly in Athens declared war against

Alexander's successor, Antipon. Aristotle was consideredan anti-Athenian, pro-Macedonian, and so he wascharged with impiety. Aristotle went into voluntary exile to

Chalcis, where he died of a digestive ailment in 322 B.C.,at the age of 63.

Legacy of Aristotle: Aristotle's philosophy, logic, science, metaphysics, ethics, politics andsystem of deductive reasoning have been of inestimable importance ever since. Aristotle'ssyllogism is at the basis of deductive reasoning. A textbook example of a syllogism is:

Major Premise:All humans are mortal.Minor Premise:Socrates is a human.
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Conclusion:Socrates is mortal.

OTHER PHILOSOPHERS

CONFUCIUS(551479 BC)

Reported By:_____________________________________Confuciuswas a Chinese teacher, editor, politician, andphilosopher of the Spring and Autumn Period ofChinesehistory.

The philosophy of Confucius emphasized personal andgovernmental morality, correctness of socialrelationships, justice and sincerity. His followerscompeted successfully with many other schools duringthe Hundred Schools of Thought era only to besuppressed in favor of the Legalists during the QinDynasty. Following the victory of Hanover Chuafter the

collapse of Qin, Confucius' thoughts received officialsanction and were further developed into a systemknown as Confucianism.

Confucius is traditionally credited with having authoredor edited many of the Chinese classic texts including allof the Five Classic s, but modern scholars are cautiousof attributing specific assertions to Confuciushimself. Aphorisms concerning his teachings werecompiled in The Analects, but only many years after hisdeath.

The Five Classics :

1. The Book of Change2. The Book of History3. The Book of Poetry4. Spring and Autumn5. A Book of Ceremonies

The Four Book s:

1. The Analects or Discourses of Confucius2. The Great Learning3. The Doctrine of The Mean4. The Book of Mencius

Confucius's principles had a basis in common Chinese tradition and belief. He championedstrong family loyalty, ancestor worship, respect of elders by their children (and in traditionalinterpretations) of husbands by their wives. He also recommended family as a basis for idealgovernment. He espoused the well-known principle "Do not do to others what you do notwant done to yourself", an early version of the Golden Rule.


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KARL MARX (May 5, 1818March 14, 1883)

Reported By: _____________________________________

Karl Heinrich Marx was a German philosopher,economist, historian, journalist, and revolutionary

socialist. Marx's work in economics laid the basis for thecurrent understanding of labor and its relation to capital,and has influenced much of subsequent economicthought. He published numerous books during hislifetime, the most notable being The Communis tManifesto(1848) and Das Kapital(18671894).

Born into a wealthy middle-class family in Trier, Marxstudied at the University of Bonnand the University ofBerlin, where he became interested in the philosophicalideas of the Young Hegelians. After his studies, he wrotefor a radical newspaper in Cologne, and began to workout his theory of dialectical materialism. He moved toParis in 1843, where he began writing for other radicalnewspapers and met Fredrick Engels, who wouldbecome his lifelong friend and collaborator. In 1849 hewas exiled and moved to London together with his wifeand children where he continued writing and formulatinghis theories about social and economic activity. He alsocampaigned for socialism and became a significantfigure in the International Workingmen's Association.

Marx's theories about society, economics and politics collectively known as Marxismhold that human societies progress through class struggle: aconflict between an ownership class that controls production and a dispossessed laboring class

that provides the labor for production.He called capital ismthe " dictatorship of th e bour geois ie" believing it to be run by thewealthy classes for their own benefit; and he predicted that, like previous socio-economicsystems, capitalism produced internal tensions which would lead to its self-destruction andreplacement by a new system: social ism. He argued that class antagonisms under capitalismbetween the bourgeoisie and proletariat would eventuate in the working class' conquest ofpolitical power in the form of a dictatorship of the proletariat and eventually establish a classlesssociety, socialism or communism, a society would be governed by a free association of

producers.


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MODULE 2:

EXPLAINING THE NATURE OF LOGIC

2 1 THE ESSENCE OF LOGICTHE STUDY OF LOGIC

LOGIC DEFINED NATURAL LOGIC LOGIC AS A SCIENCE MATERIAL AND FORMAL LOGIC

LIMITS OF LOGIC / THE SCOPE OF OUR STUDY

IMPORTANCE OF STUDYING LOGIC

THE IMPORTANCE OF LOGIC BENEFITS OF STUDYING LOGIC

PROPONENTS OF SYMBOLIC LOGIC

GEORGE BOOLE GOTTLOB FREGE


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KURT GODEL

2 1THE ESSENCE OF LOGICTHE STUDY OF LOGIC

Reported By:________________________________________________________________________

LOGIC DEFINED- Logiccomes from the Greek word logike, meaning thought. Aris to t le(384-322 BC) who

started the study of logic, believes that it is organon or instrument for discovering andpresenting truths.

- Logic is the instrument of all scientific investigations. Logic then is a prerequisite of allthe sciences.

NATURAL LOGIC- The ability to reason correctly is innate to man. He has the gift of common sense which

St. Thom as Aquinasdefines as the habit of the first principles.

LOGIC AS A SCIENCE.- Logic is defined as the science of correct thinking. It is the systematized study of the

reasoning process for the purpose of helping us think clearly, easily and correctly.- Logic is the formaland systematicstudy of correct th ink ingor reasoning.

1. Logic is a sciencebecause it is a body of knowledge systematically arranged anddemonstrated to be true. (Systematic)

2. In logic, thinking means inference. Irv ing M. Copidefines inference as a processby which one preposition is arrived at and affirmed on the basis of one or moreother propositions accepted as the starting point. (Correct Thinking)

3. An argument is any group of propositions of which one is claimed to follow fromthe others which are regarded as providing support or ground for the truth of thatone. The correctnessof an argument is the formal object of logic. (Formal)

MATERIAL AND FORMAL LOGIC.- Material Log ic teaches us how truths are arrived at with certitude. It provides for the

principles by which we may acquire true and certain knowledge.- Formal Logicteaches how we may be correct in the presentation of an arrangement. It

gives us the principles and rules of logical thinking.- Every argument has matter and form. The matter refers to the thought-content of the

propositions. The formrefers to the structure of an argument.- A sy l log ism is an oral or written discourse expressive of an argument. It is the logical

form of an argument.

LIMITS OF LOGIC / THE SCOPE OF OUR STUDY

Reported By:________________________________________________________________________

Logic provides man with the skill and power of good reasoning. Inferential Thinking is a complexprocess involving three distinct mental operations:

Simple Apprehensionis the act of the mind by which we grasp the essence of a thing.(Concept or Idea)Judgmentis the act of mind by which we compare two concepts and declare them to beeither in agreement or disagreement with each other. (Proposition)


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Reasoningis the act of the mind by which we derive new truths from what is previouslyassumed to be true. (Inference)

IMPORTANCE OF STUDYING LOGIC

Reported By:________________________________________________________________________

THE IMPORTANCE OF LOGIC:

1. The intellect separates man from the beasts. But if reason is superior power, logic is itsdynamo. Logic, therefore, is important since it contributes to the quality of human life.

2. Logic, besides, contributes to the growth of the individual. Logic, therefore, builds self-confidence, provides a feeling of direction, and gives the assurance of being in control ofones situation.

3. The practice of a profession presupposes the art of creative thinking. The ability to seethings in their proper perspective spells competence. It is the mark of intelligence.

BENEFITS OF STUDYING LOGIC:1. Ability to think clearly, systematically and critically2. Self-confidence when arguing with somebody3. Capacity to correct wrong arguments and to avoid them

4. Being broad-minded, sensible, reasonable, and practical in dealing and establishingrelationships with people.

PROPONENTS OF SYMBOLIC LOGIC

GEORGE BOOLE(November 2, 1815December 8, 1864)

Reported By:________________________________________________________________________

George Boolewas an English mathematician, philosopher and logician. He worked in the fieldsof differential equations and algebraic logic, and is now best known as the author of The Lawsof Thought. As the inventor of the prototype of what is now called Boolean L ogic, whichbecame the basis of the modern digital computer, Boole is regarded in hindsight as a founder ofthe field of computer science.

In 1847, Boole published the pamphlet MathematicalAnalysis of Logic. He later regarded it as a flawedexposition of his logical system, and wantedAnInvestigation of the Laws of Thought (1854), on Whichare Founded the Mathematical Theories of Logic andProbabilities to be seen as the mature statement of hisviews. Boole's initial involvement in logic was promptedby a current debate onquantification, betweenSirWilliam Hamilton who supported the theory of"quantification of the predicate", and Boole's supporter,

Augustus De Morgan who advanced a version ofDeMorgan duality,as it is now called. Boole's approach wasultimately much further reaching than either sides in thecontroversy. It founded what was first known as the"algebra of logic" tradition.

Boole did not regard logic as a branch of mathematics, but he provided a general symbolicmethod of logical inference.Boole proposed that logical propositions should be expressed by
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means of algebraic equations. Algebraic manipulation of the symbols in the equations wouldprovide a fail-safe method of logical deduction: i.e. logic is reduced to a type of algebra.

GOTTLOB FREGE (November 8, 1848July 26, 1925)

Reported By: _______________________________________d

By: CENTURY GOTHICFriedrich Ludwig Gottlob Fregewas a Germanmathematician,logician andphilosopher. He is consideredto be One of the Founders of Modern Logicand made majorcontributions to the foundations of mathematics. He isgenerally considered to be the Father ofAnalyticPhilosophy, for his writings on the philosophy of languageand mathematics. While he was mainly ignored by theintellectual world when he published his writings,GiuseppePeano(18581932) andBertrand Russell (18721970)introduced his work to later generations of logicians andphilosophers.

KURT GDEL (April 28, 1906January 14, 1978)

Reported By: ________________________________________

Reported By: CENTURY GOTHICKurt Friedrich Gdel was an Austrian logician,mathematician, and philosopher. Considered with Aristotleand Fregeto be one of the most significant logicians inhuman history, Gdel made an immense impact uponscientific and philosophical thinking in the 20th century, a

time when others such as Bertrand Russell, A.N.Whitehead, and David Hilbertwere pioneering the use oflogic and set theory to understand the foundations ofmathematics.

Gdel published his two incompleteness theorems in 1931when he was 25 years old, one year after finishing hisdoctorate at the University of Vienna.

The first incompleteness theorem states that for any self-consistent recursive axiomaticsystem powerful enough to describe the arithmetic of the natural numbers, there are truepropositions about the naturals that cannot be proved from the axioms. To prove this theorem,

Gdel developed a technique now known as Gdel num bering, which codes formalexpressions as natural numbers. He also made important contributions to proof theory byclarifying the connections between classical logic, intuitionistic logic, and modal logic.
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MODULE 3:

DIFFERENTIATING IDEAS AND TERMS

3 1 FORMING AN IDEAFORMING IDEAS & THE FACTS

COMMON DENOMINATOR ANDINDIVIDUATING NOTES SIMPLE APPREHENSION

CHARACTERISTICS OF CONCEPTS/IDEAS IDEA CONCEPTS OF THE FIRST & SECOND INTENTION CONCRETE ANDABSTRACT CONCEPTS

PROPERTIES OF AN IDEA COMPREHENSION EXTENSION

3 2 CLASSIFYING TERMSTERMS DEFINED TERMS

THE CONCEPT AS A SIGN

KINDS OF TERMS TERMS ACCORDING TO QUANTITY TERMS ACCORDING TO DEFINITENESS OF MEANING TEMRS ACCORDING TO INCOMPATIBILITY

3 3 UNDERSTANDING DEFINITION AND ITS FEATURES


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TERMS AS DEFINITION

TWO KINDS OF DEFINITIONS

RULES OF A GOOD DEFINITION

3 1FORMING AN IDEAFORMING IDEAS & THE FACTSReported By:________________________________________________________________________

COMMON DENOMINATOR- This single characteristic found or shared in common (Similarities)

INDIVIDUATING NOTES- The other characteristics that never affect the common denominator (Differences)

SIMPLE APPREHENSION- The mental process by which we grasp the general meaning of a thing without affirming

or denying anything about it.- This is a mental act in which the mind perceives or notices something. This something

being perceived or noticed is what we call a concept or an idea. Forming an ideainvolves the following:

ATTENTIONthis is the activity of the mind in which it focuses on something that isbeing perceivedor noticed.

COMPARISONthis happens when the mind notices the similarities and differencesof the characteristics of the things being focused on.

ABSTRACTION the activity of the mind by which it singles out a characteristic orseveral characteristicsof the object or thing being focused on.Types of Abstraction:o Formal Abstract ion withdraws a form or formal quality from a thing which is

either material or immaterial.o Total Abstract ion withdraws a universal nature or essence from particulars or

individuals.

CHARACTERISTICS OF CONCEPTS / IDEA

Reported By:________________________________________________________________________

IDEA- An idea is a representation of a wholeness of a thing; synonymous words are concept,

notion, or impression.- The idea answers the question what. The what-ness of a thing is the essence of the

thing.- The essence of a thing is what constitutes it to be what it is in itself. The mental

expression of an essence or quiddity is what we call the concept.

CONCEPTS OF THE FIRST & SECOND INTENTIONIntention refers to the act of the mind representing reality.

First Intention is a concept presenting the nature or quality of a thing in itself. Itpresents to us what something is in the realm of physical realities.

Man is capable of abstract reasoning.Man is endowed with body and soul.


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Second Intention is a concept which presents the mode or manner how the mindunderstands such nature or quality as a logical reality.

Man is a species.Man is a universal.

CONCERTE AND ABSTRACT CONCEPTS

Concrete Concept signifies a nature or quality as found residing in an individual orsubject.Examples: house friend chair

dog flower father

Abstract Conceptsignifies a nature or quality as though it exists on its own right andapart from the individual or subject.Examples: manhood animality

friendship freedomroyalty

PROPERTIES OF AN IDEA

Reported By:________________________________________________________________________

Comprehension / Connotation (Common Nouns)- the sum total of notes by which a thing is known. Notesrefer to those essential attributes

which constitute the nature of a thing.- includes the thoughts, features, characteristics, or attributes that, when collated,

constitute the nature of a thing or idea.Extension / Denotation (Proper Nouns)

- the sum total of real things or individuals to which the concept applies. The individuals,falling within the comprehension of a concept, are said to be the inferiorsof that concept.

- refers to the radius or bounds of the thing or object that an idea may cover.

Comprehension and Extension are reciprocal. They are also inversely proportional to eachother. Thus, the greater the comprehension, the lesser the extension, and vice versa.

Comprehension ExtensionSubstance spirits, minerals, plants, beasts, menMaterial substance minerals, plants, beasts, menLiving material substance plants, beasts, menSentient living material substance beasts, menRational sentient living material substance men


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3 2CLASSIFYING TERMSTERMS DEFINED

Reported By:________________________________________________________________________

TERM- Balsicas & Molano (1999) define term as a sensible arbitrary sign which expresses an

idea and the reality which the idea represents in the mind.- Timberza (2000) explains term as the verbal expression of an idea. It may be

understood as an idea or group of ideas expressed in words.- Pion (1973) maintains that terms express concepts as sensible and conventional signs.

A termis the sensible conventional sign of a concept.

a) A term is sensible, because being material, it is perceptible to the sensesb) A term is conventionalbecause it is a sort of name or label coined by men and its

usage depends upon convention or tradition.c) A term is a sign because it represents a concept and through the concept, it

represents reality.

THE CONCEPT AS A SIGNA signis anything which leads us to be aware of something else.

1. Natural Signsare those that by their nature signify something else.Examples: smokefire

feverinfectionfootprintanimal

laughterjoy2. Conventional Signs are those by convention or tradition are assigned to signify

something.Examples: flags

traffic signs and billboardsmilitary patchesschool uniforms

3. Formal / Accidental Signsare those that do not only signify things but explain them tobe what they are.Examples: pictures, concepts

KINDS OF TERMS

Reported By:________________________________________________________________________

A. CONCEPTS ACCORDING TO EXTENSION(TERMS ACCORDING TO QUANTITY)

1. Singular

Proper Nouns - signifies one specific individual

Superlatives


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DemonstrativesThis, That, These, Those

Collective Nounssignifies a group or collectionExamples: family corporation

class societyarmy

ArticlesA, An, The

2. Particularterm applies to a part or portion of a totality

Indefinite Pronouns - signifies but a part or portion of the total extension of suchconcept.

Examples: some both severalfew most majority

NumbersExamples: a number of books

ten books

3. Universal term applies to all the individuals comprising a whole; signifies all theindividuals within the extension of such concept.

Examples: all everybody noneeach nobody nothing

B. CONCEPTS ACCORDING TO COMPREHENSION(TERMS ACCORDING TO DEFINITENESS OF MEANING)

1. Univocal signifies a feature which is shared by different individuals or subjects in exactly the

same way a term having one fixed meaning or comprehension include the so-called technical terms

Examples: Photosynthesis Anthropology

2. Equivocal a term having two or several unrelated meanings

Example: pitcher a baseball player a jar or container for holding a liquid

3. Analogous signifies a feature which applies to several individuals or subjects in a partly the

same and partly different manner a term whose meaning is applied to several objects or individuals, called inferiors, in

a partly similar and partly different senseExamples: head

part of our human anatomy which encloses the brain

the chief of a department the leader of a group the mastermind of a plan or project

intel l igent (intr insic)

Dan, Doc, Noemi, Pilargolden (extr insic)

a statue a talent


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an event a person

father (proport io nal i ty)

a man who begets a child a priest

To die is to rest. (attribution)

the similarity of death to inactivity or rest

C. CONCEPTS ACCORDING TO RELATION(TEMRS ACCORDING TO INCOMPATIBILITY)

1. Identicalthose having the same comprehension and extensionExamples: manrational animal

GodSupreme Beinglawyerattorney

2. Similarthose having the same extension but different comprehensionExamples: writerjournalist

teacherprofessor

3. Compatible those expressing features which may be present simultaneously in oneindividual or subjectExamples: rich and humble

intelligent and beautifultall, dark and handsome

4. Incompatible those expressing features which cannot be present together andsimultaneously in one individual or subjectExamples: sick and healthy

rich and poorbeautiful and ugly

5. Relative / Correlative those that express a feature of a thing which cannot be thought

of without implying anotherExamples: slavemaster

husbandwifeparentschildrensubjectruler

6. Privative those which express the absence or lack of perfection in an individual orsubjectExamples: blindness

deathignorance

7. Contradictorythose so related that one is the simple negation of the other

Examples: mannon-manmortalimmortalsomethingnothinghonordishonorholyunholydefiniteindefinitelogicalillogical


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8. Contrarythose that express the extreme opposites in a given category or series of thesame classExamples: expensivecheap

firstlastleftrightemptyfull

3 3 UNDERSTANDING DEFINITION AND ITS FEATURESTERMS AS DEFINITIONS

Reported By:________________________________________________________________________

DEFINITION- A defini t ion is a statement that gives the meaning of a term. The word definition is

derived from the Latin definirewhich means to enclose within limits.

TYPES OF DEFINITIONS / TWO KINDS OF DEFINITIONS)

1. Nominalmerely points out what the term stands for, without explaining what it is initself.

Etymology states the origin or root word of a symbolExample: Philosophy

Greekphilo-love, sophia-wisdomlove of wisdom

Synonympresents another word, more popular or easily recognizable, to clarify agiven termExamples: proprietorowner

magistratejudge

ladboy Descript ionprovides a description of a thing as to its physical appearance

Example: treea living being having roots,a single trunk,several branches and leaves

Exampleoffers a sample, facsimile, or picture of the thing referred to.

2. Form al / Realnot only declares what thing is signified but explains what is its nature;also called Essential Definitionsince it explains the essence of a thing

Proxim ate genusthe nearest class to which a thing is classifiedSpecif ic dif ferencethat aspect which differentiates a thing from another belongingto the same class

Term Genus DifferentiaProfessor a scholarly teacher being usually an expert in arts or sciencesLogic a philosophical study used in valid reasoning

RULES OF A GOOD DEFINITION

Reported By:________________________________________________________________________

A defini t ion must be brief. Thus, a definition must be short unless it is extremelynecessary to provide details to sufficiently explain a thing.


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A defini t ion m ust be clear.A definition, therefore, should unravel the nature of a thing andshould not obscure it.

A defini t ion mus t be posit ive.A definition should tell us what a thing is and what it is not.

A defini t ion m ust be adequate.This means that the definition states exactly the nature ofthe thing defined so that in effect, they are convertible or co-extensive.

A defini t ion m ust no t contain the term or feature defined.This is obvious, because wecannot define a term by itself. This results in a tautologous definitionwhich is an error.

MODULE 4:

MAKING PROPOSITION & JUDGMENT

4 1 UNDERSTANDING JUDGMENT AND PROPOSITIONTHE MENTAL ACT OF JUDGMENT

JUDGMENT PREREQUISITES IN MAKING JUDGMENT

THE MATERIAL STRUCTURE OF PROPOSITION PROPOSITION

ELEMENTS OF A PROPOSITION KINDS OF PROPOSITIONS

TYPES OF CATEGORICAL PROPOSITIONS ACCORDING TO THE EXTENSION OF THE SUBJECT ACCORDING TO THE QUALITY OF THE COPULA ACCORDING TO THE MATTER AFFIRMED OR DENIED ACCORDING TO ITS THOUGHT-CONTENT

SYMBOLS OF PROPOSITIONS SYMBOLS OF THE FOUR CATEGORICALS FOUR TYPES OF PROPOSITIONS IN ARISTOTELIAN LOGIC THE LOGICAL DIAGRAM OF PROPOSITIONS

4 2 OPPOSING LOGICAL PROPOSITIONOPPOSITIONFOUR KINDS OF LOGICAL OPPOSITION

CONTRADICTORY CONTRARY SUBCONTRARY SUBALTERN


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4 3 APPLYING LOGICAL EQUIVALENCEEDUCTIONFOUR KINDS OF LOGICAL EQUIVALENCE

CONVERSION OBVERSION

CONTRAPOSITION INVERSION

4.1 UNDERSTANDING JUDGMENT AND PROPOSITIONTHE MENTAL ACT OF JUDGMENT

Reported By:________________________________________________________________________

JUDGMENT- The act of the mind in pronouncing the objective identity, or non-identity of one concept

from another (Pion, 1973)- The mental act of affirming or denying the relationship between two concepts or

enunciations (McCall)

PREREQUISITES IN MAKING JUDGMENT1. There must be at least two or more conceptsthat exist.2. The mind must examine the sim ilari t ies and differencesto verify the truth or falsity of

the concept.3. The mind must lay down its acceptance and reject ionof the ideas.

THE MATERIAL STRUCTURE OF PROPOSITION

Reported By:________________________________________________________________________

PROPOSITION- The verbal expression of m ental judgm ent, affirming or denying the identity or non-

identity of two concepts; also known as enunciat ion, or statement, or sentence- It is the combination of matterand form, such as:

a) The movie is interesting.b) His father is not a lawyer.

ELEMENTS OF A PROPOSITION

From the structural point of law, a proposition is composed of the Subject, the Copula, and thePredicate. It follows this pattern: S-c-P.

1. Subjectthe one which is affirmed or denied

2. Predicatethe action that affirms or denies the subject3. Copulalinks the subject to the verb

A logical proposition is a declarat ive sentence. Obviously, not every sentence is a logicalpropos i t ion, expressive of a judgment.

Man thinks.

Change the verb to present tense progressive.Man is thinking.

Incorporate the verb in a phrase.


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Man is a thinking animal.

Change the verb into a noun.Man is a thinker.

Change the verb into a relative clause.Man is an animal that thinks.

KINDS OF PROPOSITIONS

1. Categorical: A categorical proposition unites or separates two concepts by means of thelinking verb to be.Examples:

a) Every good action ismeritorious.b) Some sharks areman-eaters.

2. Hypothetical: A hypothetical proposition unites or separates, not two concepts, but two

enunciations by means of a non-verb copula. Often, a conjunction is used instead, suchas: i f, and either-or. Examples:a) If it is a car, it has a motor.b) A proposition is eithertrue orfalse.

TYPES OF CATEGORICAL PROPOSITIONS

Reported By:________________________________________________________________________

A. Acco rding to the Extension of the Subject

**Quantityrefers to the number of referents to which the subject term is applied.

1. Singular Propo sit ion. This is a proposition whose subject is a singular concept, that

is, it refers to one specific individual.( Names, Demonstratives, Title Positions )

a) Christopheris the valedictorian of the class.b) This bookis very interesting.c) The Head of the Science Departmentis my teacher.

2. Part icular Propos it ion. This is a proposition whose subject stands for a particularconcept, that is, to a portion or part of a given totality.

( Some, Several, A number, Majority )a) A number of studentsvolunteered for the job.b) Some guestsarrived early.c) Several itemsare missing from the room.

3. Universal Propos it ion. This is a proposition whose subject stands for a universalconcept, that is, to all the inferiors or individuals of the extension of such concept.( All, Every, Each, Nobody, None )

a) All menare mortals.b) Every fatheris proud of his children.c) Each scholarwas given a citation.


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4. Indefin i te Propos it ion. This is a proposition whose subject stands for an indefinitenumber of individuals. It is so designated precisely because it does not have anyquantifying particle to signify its extension.

( Collective Nouns, Articles )a) Filipinosare deeply religious.b) The childrenare playing in the yard.

B. Acco rding to the Quali ty of the Copula

**Qualityrefers to the state of being, or it answers the question of what kind.

1. Aff i rmat ive. This is a categorical proposition which affirms the existing relationshipbetween the subject and the predicate.a) Some drivers arereckless.

2. Negative. This is a categorical proposition which denies the relationship betweensubject and predicate.a) The teacher is notstrict.

C. Acco rding to the Matter Aff irmed or Denied

1. Simple. This is a categorical proposition which unites or separates only twoconcepts or terms.a) Drug Addictionis a menace to society.b) AIDSis incurable.c) Evais a good mother.

2. Compound. This is a categorical proposition which expresses a single enunciationtwo or more propositions.a) Heis an intelligent, dashing fellow.b) Mr. Umali is a loyal friend and a good teacher.c) Some students are diligent, but others are not.

D. Acco rding to its Thought -Content

1. True. A categorical proposition whose thought-content agrees with objective reality issaid to be factual or true.a) Manis a rational animal.b) A trianglehas three sides.

2. False. A categorical proposition whose thought-content does not agree withobjective reality is false.a) A buildingis a living thing.b) Amorsolois anAmerican painter.

SYMBOLS OF PROPOSITIONS

Reported By:________________________________________________________________________

SYMBOLS OF THE FOUR CATEGORICALS

1. The A Proposition is an aff irmative proposition with a universal or potentiallyuniversal subject. Its logical form is ALL S is P.a) All professorsare professionals.b) Every rightis limited.

2. The EProposition is a negativeproposition with a universal or potentially universalsubject. Its logical form is NO S is P.


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a) All saintsare not sinners.b) No man is an angel.

3. The IProposition is an aff irmativeproposition with a part icularor indefinite subject.Its logical form is SOME S is P.a) Some politiciansare criminals.

b) Few studentsare in the Deans List.4. The "OProposition is a negativeproposition with a part icularor indefinite subject. Its

logical form is SOME S is not P.a) Some criminalsare not bad.b) Not all women are mothers.

FOUR TYPES OF PROPOSITIONS IN ARISTOTELIAN LOGIC

Reported By:________________________________________________________________________

Code Letter Quantity Quality Example

A Universal Affirmative All men are mortal.

E Universal Negative No men are immortal.I Particular Affirmative Some men are weak.O Particular Negative Some men are not moral.

The letters Aand Iare derived from the vowels of the latin word affirmo which means I affirm.Both letters stand for affirmative propositions. A stands for universal affirmative. I stands for

particular affirmativepropositions.

The letters Eand Oare derived from the vowels of the latin word negowhich means I deny.Both letters stand for negative propositions. E stands for universal affirmative. O stands forparticular negative propositions.

These are the only accepted types of proposition in Aristotelian logic. They also have thefollowing Latin verse being used to remember the code letters:

Asserit A, negat E, verum generaliter ambo;Asserit I, negat O, sed particulariter ambo.

Code Letter Quantity Quality Proposition Modern Notation

Asp Universal Affirmative All S are P x(S(x)P(x))

Esp Universal Negative No S are P x(S(x)P(x))

Isp Particular Affirmative Some S are P x(S(x)P(x))

Osp Particular Negative Some S are not P x(S(x)P(x)

THE LOGICAL DIAGRAM OF PROPOSITIONS

Reported By:________________________________________________________________________

Leonhard Euler, a Swiss Mathematician, introduced the use of logical diagram to illustrate therelationship of the Subject and the Predicate on the basis of their respective extension.


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4.2 OPPOSING LOGICAL PROPOSITIONOPPOSITION

- The relation of being against or repugnant to something that is already given- Happens if the pair of propositions given is said to be in contrast- The relative position of each one of the four types of opposites is illustrated in the

square of oppos i t ion

FOUR KINDS OF LOGICAL OPPOSITION

Reported By:________________________________________________________________________


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A. Contradictory.The propositions differ in both quantity and quality.Rules of Contradictories:

1. If one is true, the other is false.2. If one is false, the other is true.

Examples:A-O If Every Filipino is Asian is true,

Then Some Filipinos are not Asians is false.E-I If Some cows are writersis false,

Then No cow is a writer is true.

B. Contrary.Both differ in quality but not in quantity. They are both universal.Rules of Contraries:

1. If one is true, the other is false.2. If one is false, the other is doubtful.3. Both can be false at the same time, but never true at the same time.

Examples:A-E If Every fish is aquatic is true,

Then No fish is aquatic is false.E-A If No cat is black is false,

Then All cats are black is doubtful, that is either true or false.

C. Subcontrary.Propositions differ in quality but not in quantity. They are both p art icular.

Rules of Subcontraries:1. If one is false, the other is true.2. If one is true, the other is doubtful.Examples:I-O If Some catholics are protestants is false,

Then Some catholics are not protestants is true.O-I If Some prisoners are guilty is true,

Then Some prisoners are not guilty is doubtful,in form.

D. Subaltern. The propositions differ in quantity but not in quality.Rules of Subalterns:1. If the universal is true, the particular is true; but if the universal is false, the particular

is doubtful.2. If the particular is true, the universal is doubtful; but if the particular is false, the

universal is true.Examples:A-I Since All voters are citizens is true,

Then Some voters are citizens is true.E-O Since No accountant is a lawyer is false,

Then Some accountants are not lawyers is doubtful, in form only.


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4.3 APPLYING LOGICAL EQUIVALENCEEQUIPOLLENCE / EQUIVALENCE

- A method of rendering in another way the truth or falsity expressed in a given proposition

EDUCTION- The formulation of a new proposition by the interchange of the subject and predicate of

an original proposition and/or by the use or removal of negatives. (Bachhuber)

FOUR KINDS OF LOGICAL EQUIVALENCE

Reported By:________________________________________________________________________

A. Conversion. The re-phrasing of the truth of a given proposition by interchanging thesubject and the predicate, without over-extending the quantity of either terms.

Original Proposition: ConvertendNew Formulation: Converse

Rules of Conversion:1. Interchange S and P without over-extending their quantity.2. Retain the quality of the copula of the convertend.

Types of Conversion:

1. Simple Conversion takes place when the quantity of the converse is the same asthat of the convertend. This happens only with E and I propositions.

Examples:E No dog is a cat, becomes No cat is a dog. I Some men are teachers, becomes Some teachers are men.

2. Part ial or Ac cidental Conversiontakes place when the quantity of the converse isdifferent from that of the convertend. This is possible with the A proposition.Example:

A All actors are artists, becomes Some artists are actors.


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B. Obversion. The method of rephrasing the truth of a given proposition by changing thequality of the copula. All the four categorical proposit ions m ay be obverted.

Original Proposition: ObvertendNew Formulation: Obverse

Rules of Obversion:

1. Change the quality of the copula of the obvertend.2. Change the quality of the predicate from positive to negative, and vice versa.3. Retain the quantity of the obvertend.

Examples:A-E Every man is rational, becomes No man is irrational.E-A No goat is carnivorous, becomes All goats are non-carnivorous.I-O Some men are monks, becomes Some men are not non-monks.O-I Some leaders are not honest, becomes Some leaders are dishonest.

C. Contraposit ion. The method of rephrasing the truth of a given proposition by combiningthe processes of obversion and conversion.

Original Proposition: Contraponend

New Formulation: Contraposit

Types of Contraposition:

1. Simple Contraposit ion is possible when the contraponend is either the A, the E, orthe Opropositions. The I proposit ion has no con traposit .Procedures:

Obvert the original proposition. Convert the obverse.

Examples:

A-E Contraponend: All men are rational.Obversion: No man is irrational.

Conversion: No irrational (being) is man.

E-I Contraponend: No stones are bread.Obversion: All stones are non-bread.Conversion: Some non-bread are stones.

O-I Contraponend: Some toys are not mechanical.Obversion: Some toys are non-mechanical.Conversion: Some non-mechanical (things) are toys.

2. Comp lete Contraposit ionmakes possible the changing of the A to A, of the E toO, and of the O to O.Procedures:

Obvert. Convert the obverse. Obvert the converse.

Examples:

A-A Contraponend: Every man is mortal.Obversion: No man is immortal.Conversion: No immortal is man.Obversion: Every immortal is non-man.


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E-O Contraponend: No dog is a cat.Obversion: Every dog is non-cat.Conversion: Some non-cats are dogs.

` Obversion: Some non-cats are not non-dogs.

D. Inversion. The value of this method consists in helping us to be alert to the quantity andquality of the subject, and to the quality of the copula. I and O prop osit ions h ave noinverse.

Original Proposition: InvertendNew Formulation: Inverse

Types of Inversion:

1. Simple Inversionapplies only to Aand Epropositions.Procedures:

Change the subject of the invertend to its contradiction. Change the quantity of the invertend. Change the quality of the copula. Retain the original predicate.

Examples:A-O Every man is rational, becomes Some non-man is not rational.E-I No man is a cow, becomes Some non-men are cows.

2. Comp lete Inversionlikewise applies to Aand Epropositions.Procedures:

Change the subject to its contradiction. Change the quantity of the proposition. Retain the quality of the copula. Change the predicate to its contradiction.

Examples:

A-I Every man is rational, becomes Some non-man are non-rational.E-O No man is a cow, becomes Some non-men are non-cows.

The following chart gives the converse, obverse and contrapositive of each of the fourcategorical propositions and indicates which of those transformations are NOT VALID.

A E I O

Propos i t ion All S are P No S are P Some S are P Some S are not P

ConverseAll P are SNOT VALID

No P are S Some P are SSome P are not S

NOT VALID

ObverseNo S are non-P All S are non-P

Some S are not

non-P Some S are non-P

Contraposit iveAll non-P are

non-S

No non-P arenon-S

NOT VALID

Some non-P arenon-S

NOT VALID

Some non-P arenot non-S


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5 1 VALIDATING THE TRUTHTHE SYLLOGISM: ITS FORM AND MATTERKINDS OF REASONING

5 2 FORMING A CATEGORICAL SYLLOGISMRULES ON TERMSRULES ON PROPOSITIONS

5 3 UNDERSTANDING MOODS AND FIGURESMOODS & FIGURES DEFINED

5 4 DISTINGUISHING HYPOTHETICAL SYLLOGISMCONDITIONAL SYLLOGISMDISJUNCTIVE SYLLOGISMCONJUCTIVE SYLLOGISM

5.1 VALIDATING THE TRUTHReported By:________________________________________________________________________

REASONING

- A mental process that compares two similar propositions and out of these propositions, aconclusion is drawn or formed.Kinds of Reasoning:

Deductive Reasoning forms a conclusion out of a generally accepted fact fromgeneral/universal to particular.

Inductive Reasoning forms a conclusion from a particular to a universal or generalinstance or fact, from particular to general.

INFERENCE- A process by which one proposition is arrived at and affirmed or denied on the basis of one

or more propositions accepted as the starting point of the process. ** The result of the act of reasoning.

Every A is B,

But every X is A.Therefore, every X is B.

THE SYLLOGISM: ITS FORM AND MATTER

SYLLOGISM- An oral or written discourse showing the agreement or disagreement between two terms on

the basis of their respective relation to a common third term.** The verbal symbol of an inference.

CATEGORICAL SYLLOGISM


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- An argument consisting of exactly three categorical propositions (two premises and aconclusion) in which there appear a total of exactly three categorical terms, each of which isused exactly twice.

- One of those terms must be used as the subject term of the conclusion of the syllogism, andwe call it the minor termof the syllogism as a whole. Themajor termof the syllogism iswhatever is employed as the predicate term of its conclusion. The third term in the syllogism

does not occur in the conclusion at all, but must be employed in somewhere in each of itspremises; hence, we call it themiddle term.

- Since one of the premises of the syllogism must be a categorical proposition that affirmssome relation between its middle and major terms, we call that themajor premiseof thesyllogism. The other premise, which links the middle and minor terms, we call theminor

premise.Every man is rational, Major Premise/Antecedent

(M)

But every Filipino is a man. Minor Premise/Antecedent(M)

Therefore, every Filipino is rational. Conclusion/Consequent(S) (P)

VALID SYLLOGISM- A syllogism is correct when it is in conformity with the rules of logic. It is true when the

propositions employed are expressive of truths. FORMALLY CORRECTcorrect as to form but false as to content

MATERIALLY TRUEtrue as to its content but wrong as to its form

INVALID SYLLOGISM- A syllogism which is correct in form but false in its content or matter.

5.2 FORMING A CATEGORICAL SYLLOGISMReported By:________________________________________________________________________

THE RULES AND FALLACIES OF CATEGORICAL SYLLOGISM

Rule 1: The middle term must be distributed at least once.Fallacy: Undistributed middle

Example:

All sharks are fishAll salmon are fishAll salmon are sharks

Justification: The middle term is what connects the major and the minor term. If the middle termis never distributed, then the major and minor terms might be related to different parts of the Mclass, thus giving no common ground to relate S and P.

Rule 2: If a term is distributed in the conclusion,then it must be distributed in a premise.

Fallacy: Illicit Major; Illicit MinorExamples:

All horses are animalsSome dogs are not horsesSome dogs are not animals

All tigers are mammals
http://www.philosophypages.com/dy/m7.htm#minthttp://www.philosophypages.com/dy/m7.htm#minthttp://www.philosophypages.com/dy/m.htm#majthttp://www.philosophypages.com/dy/m.htm#majthttp://www.philosophypages.com/dy/m.htm#majthttp://www.philosophypages.com/dy/m7.htm#midthttp://www.philosophypages.com/dy/m7.htm#midthttp://www.philosophypages.com/dy/m7.htm#midthttp://www.philosophypages.com/dy/m.htm#majphttp://www.philosophypages.com/dy/m.htm#majphttp://www.philosophypages.com/dy/m.htm#majphttp://www.philosophypages.com/dy/m7.htm#minphttp://www.philosophypages.com/dy/m7.htm#minphttp://www.philosophypages.com/dy/m7.htm#minphttp://www.philosophypages.com/dy/m7.htm#minphttp://www.philosophypages.com/dy/m7.htm#minphttp://www.philosophypages.com/dy/m7.htm#minphttp://www.philosophypages.com/dy/m.htm#majphttp://www.philosophypages.com/dy/m7.htm#midthttp://www.philosophypages.com/dy/m.htm#majthttp://www.philosophypages.com/dy/m7.htm#mint


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All mammals areanimalsAll animals are tigers

Justification: When a term is distributed in the conclusion, lets say that P is distributed, then thatterm is saying something about every member of the P class. If that same term is NOTdistributed in the major premise, then the major premise is saying something about only somemembers of the P class. Remember that the minor premise says nothing about the P class.Therefore, the conclusion contains information that is not contained in the premises, making theargument invalid.

Rule 3: Two negative premises are not allowed.Fallacy: Exclusive Premises

Example:

No fish are mammalsSome dogs are not fishSome dogs are not mammals

Justification: If the premises are both negative, then the relationship between S and P is denied.

The conclusion cannot, therefore, say anything in a positive fashion. That information goesbeyond what is contained in the premises.

Rule 4: A negative premise requires a negative conclusion,and a negative conclusion requires a negative premise.**Alternate rendering: Any syllogism having exactly one negative statement is invalid.

Fallacy: Drawing an affirmative conclusion from a negative premise,or drawing a negative conclusion from an affirmative premise.

Example:

All crows are birdsSome wolves are not crowsSome wolves are birds

Justification: Two directions, here. Take a positive conclusion from one negative premise. Theconclusion states that the S class is either wholly or partially contained in the P class. The onlyway that this can happen is if the S class is either partially or fully contained in the M class(remember, the middle term relates the two) and the M class fully contained in the P class.Negative statements cannot establish this relationship, so a valid conclusion cannot follow. Takea negative conclusion. It asserts that the S class is separated in whole or in part from the Pclass. If both premises are affirmative, no separation can be established, only connections.Thus, a negative conclusion cannot follow from positive premises.

Note: These first four rules working together indicate that any syllogism with two particular premises is invalid.

Rule 5: If both premises are universal, the conclusion cannot be particular.

Fallacy: Existential FallacyExample:

All mammals are animalsAll tigers are mammalsSome tigers are animals

Justification: On the Boolean model, Universal statements make no claims about existencewhile particular ones do. Thus, if the syllogism has universal premises, they necessarily saynothing about existence. Yet if the conclusion is particular, then it does say something about


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existence. In which case, the conclusion contains more information than the premises do,thereby making it invalid.

THE ARISTOTELIAN STANDPOINT

Any syllogism that violates any of the first four rules is invalid from either standpoint. If a

syllogism, though, violates only rule 5, it is then valid from the Aristotelian standpoint, providedthat the conditional existence is fulfilled. Thus, in the example above, since tigers exist, thissyllogism is valid from the Aristotelian point of view.

On the other hand, consider this substitution instance:

All mammals are animalsAll unicorns are mammalsSome unicorns are animals

Since "unicorns" do not exist, the condition is not fulfilled, and this syllogism is invalid fromeither perspective.

All Md are PAll Sdare M

Some S are P

No Mdare PdAll Mdare S

Some S are not Pd

All Pdare MAll Mdare S

Some S are P

5.3 UNDERSTANDING MOODS AND FIGURESReported By:________________________________________________________________________The arrangement of the four propositions--A, E, I or O--determines the mood, or orderingof the three propositions which make up the syllogism.A syllogism with all A propositions,such as those above, is one in mood AAA. One with E propositions as the major premise andconclusion and an I proposition as the minor premise would be in mood EIE. Thus the order ofpropositions determines the mood of a categorical syllogism. Since there are four kinds ofcategorical propositions and three propositions in each syllogism, there are 64 possiblesyllogistic moods. Moreover, there are 16 possible arrangements of the four kinds ofpropositions with each A, E, I or O proposition serving as the major premise :

AAA EAA IAA OAAAAE EAE IAE OAE

AAI EAI IAI OAIAAO EAO IAO OAO

AEA EEA IEA OEAAEE EEE IEE OEEAEI EEI IEI OEIAEO EEO IEO OEO


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AIA EIA IIA OIAAIE EIE IIE OIEAII EII III OIIAIO EIO IIO OIO

AOA EOA IOA OOA

AOE EOE IOE OOEAOI EOI IOI OOIAOO EOO IOO OOO

These 64 moods can be arranged in four figures, with the figure being determined by theposition of the middle term. Since the middle term cannot occur in the conclusion, there are onlyfour possible arrangements of the terms: the middle term can be the subject or predicate of themajor premise or the subject or predicate of the minor premise. The usual arrangement of thesefour figures is this:

M P P M M P P M(1) S M (2) S M (3) M S (4) M S

--- --- --- ---S P S P S P S P

Since there are 64 moods and four figures, there are 256 possible categorical syllogisms. Each of these 256 syllogisms are distinguished from one another by a distinct mood and figure.Examples (1) and (2) above are AAA-1 categorical syllogisms. Their mood is AAA and theirfigure is the first one.

5.4 DISTINGUISHING HYPOTHETICAL SYLLOGISMReported By:________________________________________________________________________

Hypothetical Syl logismis a syllogism that has a hypothetical proposition as one of its premise.

KINDS OF HYPOTHETICAL SYLLOGISM

1. Cond ition al Syllog ism (If-Then)

A Conditional Syllogism is one whose major premise is a conditional proposition.Conditional Propositions are compound propositions of which one member (the then clause)asserts something as true on the condition that the other member (the if clause) is true.

If it is raining, the roof is wet.The if clause or its equivalent is called the antecedent.

The then clause or itsequivalent is called the consequent.

2. Disjun ctiv e Syllog ism (Either-Or)

A Disjunctive Syllogism is one whose major premise is a disjunctive proposition, whoseminor premise sublates (or posits) one or more members of the major premise, and whoseconclusion posits (or sublates) the other member or members. A Disjunctive Syllogism is onethat presents various alternatives and asserts that an indeterminate one of them is true. Itconsists of two or more members joined by the conjunctions either-or. It is sometimes called analternative proposition.


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Rules for Disjunctive Syllogism:a. If the minor premise posits one or more members of the major premise, the

conclusion must sublate each of the other members.It is either rainingor not raining;but it is raining;

therefore it is not not raining.b. If the minor premise sublates one or more of the members of the major premise, the

conclusion posits the remaining members, one of which must be true. If more thanone member remains, the conclusion must be a disjunctive in the strict sense.

It is either rainingor not raining;but it is not raining;therefore it is not raining.

3. Conjunctiv e Syl logism (Not Both-And )

A Conjunctive Syllogism is one whose major premise is a conjunctive proposition, whoseminor premise posits one or more members of the major premise, and whose conclusionsublates the other member of the major premise. A Conjunctive Syllogism is one that denies the

simultaneous possibility of two alternatives.

A thing cannot both be and not be in the same respect.

Rules for Conjunctive Syllogism:a. Posit one member in the major premise and sublate the other in the conclusion.

He cannot be in Manila and Cebu at the same time;but he is now in Manila;Therefore he cannot now be in Cebu.

MODULE 6:

AVOIDING FALLACY


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6 1 UNDERSTANDING VERBAL FALLACYFALLACY OF LANGUAGE

EQUIVOCATION AMPHIBOLY

ACCENT FIGURE OF SPEECH

COMPOSITION DIVISION

6 2 UNDERSTANDING NON VERBAL FALLACYFALLACY OF CONFUSION

ACCIDENT ABSOLUTE

IGNORATIO ELENCHI FALSE CAUSE CONSEQUENT

MULTI-QUESTIONS

OTHER FORMS OF FAULTY ARGUMENTS BEGGING THE QUESTION

NON-SEQUITUR APPEAL TO IGNORANCE SUPPRESSION OF FACTS

UNFOUNDED GENERALIZATIONS

6.1 UNDERSTANDING VERBAL FALLACYReported By:________________________________________________________________________

FALLACIES- Errors in argumentation; the word comes from the Latin fallowhich means I deceive.- An argument that seems to be correct but proves to be false. If it is committed to deceive

others, it is called sophism. If committed without malice, it is called paralogism.

TYPES OF FALLACYAristotle classifies the fallacies under two general headings: the FALLACY OF

LANGUAGE, and the FALLACY OF CONFUSION.

FALLACY OF LANGUAGEVerbal Fallacy is a mistake in the use of words but not in the structure of idea in the mind

of the speaker.

1. EQUIVOCATION the fallacy of attributing two different meanings to a given term insyllogism.

Example: What is natural is good.


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But for man to err is natural.Therefore, for man to err is good.

2. AMPHIBOLYconsists of using a phrase, or manner of speech, which is ambivalent asto its meaning.

Example: He is an English Teacher.

Is he an Englishman teaching or a teacher who is teaching English?

3. ACCENT consists in giving the same meaning to words having the same or similarpronunciation or spelling.

Example: A mole is an animal.But Dina has a beautiful mole on her chin.Therefore, Dina has a beautiful animal on her chin.

4. FIGURE OF SPEECH consists of inferring a meaning from the similarity of wordstructure, or interpreting literally a figure of speech.

Example: Anybody restless is not restful.Anybody careless is not careful.

Therefore, anybody helpless is not helpful.5. COMPOSITION consists of taking a group of words or phrase as a unit instead of

taking them separately as it should be.

Example: TIP is an engineering school.But you are a student of this school.Therefore, you are an engineering student.

6. DIVISIONconsists of taking separately what should be taken as a unit.

Example: Every man is a person.But a woman is not a man.Therefore, a woman is not a person.

6.2 UNDERSTANDING NON VERBAL OR MATERIAL FALLACYReported By:___________________________________________________________________________

FALLACY OF CONFUSIONAnother word for non-verbal fallacy is material fallacy or fallacy of matter.

1. ACCIDENTconfuses the essential attribute with what is merely an accidental attributeto the nature of a thing.

Example: Filipinos are Christians.But some citizens are not Christians.

Therefore, some citizens are not Filipinos.Religious affiliation is accidental to the citizenship of an individual. A citizen is constitutedas such either by birth or by law.

2. ABSOLUTEuses a restricted principle (one which is true only under certain situations)as if it were an absolute principle (one which is true under all situations).

Example: Water can solidify.But water is liquid.Therefore, all liquids can solidify.


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3. IGNORATIO ELENCHI Elenchos means refutation. Ignoratio Elenchi meansignorance of refutation. It consists in proving something other than that which issupposed to be proved. Thus, this fallacy is also called ignoring the issue, missing thepoint, or evading the question.

Example: The supply of food is insufficient to a growing population.

But birth control regulates population growth.Therefore, birth control assures sufficiency of food supply.

Ad Hominem arguments are variations of ignoratio elenchi. They are irrelevant arguments andtherefore, do not prove a truth. They are however, very popular because they appeal to menpsychologically or emotionally.

3.1 Argument Against The Person / Argumentum ad hominem it refers to anargument which, instead of resolving the issue at hand, attacks the character ofan opponent.

The allusion to then presidential candidate Cory Aquino as walang alam and asbabae para sa kwarto lamang proved disastrous to then President FerdinandMarcos.

3.2 Argument To People / Argumentum ad populum instead of proving anissue by reason, appeals to popular sentiments, opinions, biases, idiosyncrasies,or emotions of people.

Labor Leaders seek support for a strike by hammering on the sad plight andtravails of workers in general. A newspaper, by sensationalizing a crime,describing all its gory details, provokes public indignation either against thecriminals or against indifferent public officials.

3.3 Argument To Sympathy / Argumentum ad misericordiam this is anargument that appeals to pity.

Shedding tears is one good example of this argument. Tears have a way of

melting even the most hardened heart. It is not unusual for criminals to cry andsob out a sad story in order to win a reprieve.

3.4 Argument To Authority or Dignity / Argumentum ad verecundiam Verecundiammeans shame. The argument however, is better known as appealto authority. One may argue that a certain conclusion is true because it concurs,or is, the opinion of an expert authority.

In mass media, many commercials cite the authority of certain persons, usuallymovie stars and popular athletes, to urge people to patronize a certain product.

3.5 Argument To Force / Argumentum ad baculum this means appeal to thestick. This is an argument that appeals to the use of force or threat.

Oral or written threats are arguments ad baculum. They are the favorite of streetbullies, blackmailers, robbers, rapists, and terrorists. These are arguments thatdo not need eloquence nor linguistic sophistication.

4. FALSE CAUSEconsists in attributing an effect or result to an insufficient cause.

Example: That which comes ahead produces that which follows it.But night comes ahead of day.Therefore, night causes day.


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5. CONSEQUENT consists of inferring the truth of an antecedent from the truth of theconsequent, or the falsity of the consequent from the falsity of the antecedent. Thisfallacy pertains to the use of hypothetical syllogism.

Example: If it rained, the ground is wet.But the ground is wet.

Therefore, it rained.6. MULTI-QUESTIONSthis fallacy consists in phrasing several questions as one for the

purpose of misleading a respondent to admit something he does not intend to.

Example: The question Is the president a nationalist with a sense of justice? iscomposed of two questions. The questions, therefore, is not simplyanswerable by yes or no without making proper distinction.

OTHER FORMS OF FAULTY ARGUMENTS

1. BEGGING THE QUESTIONS this is also called petition principii. It consists ofproving a conclusion by using a premise which is merely the equivalent of theconclusion.

Example: The suspect is the murderer.But Pedro is the suspect.Therefore, Pedro is guilty.

2. NON-SEQUITURan argument whose conclusion does not necessarily follow from thepremises. Strictly speaking, a non-sequitur argument is a series of unrelatedpropositions, arranged in a manner that resembles that of syllogism.

Example: Every student is desirous of learning.But all desirous of learning are diligent.Therefore, every student is diligent.

3. APPEAL TO IGNORANCEthis argument suggests that since there is no proof to the

contrary, then something must be true.

Example: Since nobody saw him commit the crime, then he did not do it.

4. SUPPRESSION OF FACTS this argument consists in withholding a vital information,or in selecting only those facts that favor ones view point.

Example: The farmer confessed to stealing a piece of rope. He did not tell the judgethat at the end of the rope was the carabao of his neighbor.

5. UNFOUNDED GENERALIZATIONS this argument consists of accepting a particulartruth as a universal and absolute truth. The data of experiences are often expressed asgeneral statement of facts.

Examples: Boys are unruly.Filipinos lack discipline.Politicians are corrupt.


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INTRODUCTION TO LOGIC: A MODULAR APPROACHEVALUATION PROJECT

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS IN

HUM 002 / ME21FB1


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SUBMITTED BY:

PATRICK G. CRUZ

BS EE

1020108

SUBMITTED TO:

PROF. RONNIE PARATI

Logic: Evaluation Project

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