Modern Skepticism

Reed Esau21-Mar-2008

bias & the informed consensus

Avoiding the traps of faulty reasoning

Modern Skepticism

Respect for reliable evidence

Traps?

Cognitive Bias

Our brains aren’t wired for objectivity

They are wired for adaption & survival

Cognitive biases are instances of evolved mental behavior

Mental shortcuts that can enable faster* decisions

or reduce distraction

*but not necessarily the best

An ExperimentFour empty wine bottles

Visible stickers ranging $5-90

Same wine goes into all bottles;

re-cork

A taste test with friends!

Expected Results?

More ‘expensive’ wine reported to taste better

Not terribly surprising

Lot of noise in this test

Can we remove the noise?

Can we measure what people actually experience, rather than what they say

they experience?

Functional MRI

The basic idea

Touch DSee C

Taste A Hear B

This has been done

Caltech & Stanford Teams

Expectations & effectiveness of medication

Why are generics less effective than name-brand drugs?

What would we expect?

The brain reacts to the wine in consistent manner, no matter its price

Subjects consistently experienced more pleasure with the ‘expensive’ wine

- or -

It’s the latter!

What’s going on?

Expectations shape our experience of the world -- what we taste, see and hear

The cortex is ‘cooking the books’ by adjusting

its inputs to sensory data

Interesting ImplicationsWe experience the

world not as it is but rather how we expect it to be.

Evidence that our brains aren’t wired

for objectivity

But what does this have to do with skepticism?

A big part of being a skeptic is compensating for our biases

Our expectations are yet another of these biases

To deny or ignore them is to risk deluding yourself

Forer Effect

Tendency to consider vague descriptions of personality to be accurate.

Confirmation Bias

When interpreting new information...

• Emphasizing that which confirms one’s preconceptions

• Ignoring that which contradicts

“Ignorance more frequently begets confidence than does

knowledge”

Charles Darwin

Dunning-KrugerEffect

those who have little knowledge tend to think that they know more

than they do

others who have much more knowledge tend to think that they know less

It gets worse!

Incompetent individuals...

tend to overestimate their own level of skill

fail to recognize genuine skill in others

fail to recognize the extremity of their inadequacy

Bias blind spot

The tendency not to compensate for one’s own biases

World of Pain

How to avoid these biases?

Study and talk about them

Review you own beliefs

Understand methods to avoid bias

Build upon expertise of others

Building upon expertise?

Understand the value and limitations of

The Informed Consensus

Informed Consensus

Theory Test Review

Body of expert opinion

Repeat

What is an ‘expert’?

“An expert is someone who knows some of the worst mistakes that can be made in

his subject, and how to avoid them.”

Werner Karl Heisenberg

Examples of Informed Consensus

Bulletproof IC

Common Descent

Relativity

Strong IC• Man landed on the

moon

• Man contributing to climate change

• Natural selection

• Smoking increases risk of heart disease

• Age of earth is 4.54By

Other ICs

• Red wine is healthy

• Government reports

• Accident investigations

• ET’s haven’t visited Earth

• Lance Armstrong won the Tour de France seven consecutive times

‘Failures’ ofInformed Consensus

Pre-Copernican Astronomy

Copernican Heliocentrism

Plate tectonics

Disputes of the IC

• Apollo moon landings were a hoax

• Vaccines cause autism

• Solar variation accounts for climate change

• Most cancers are viral-based

• WTC7 was a controlled demolition

How to evaluate?

Crafting cohesive alternative theories

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Engaging critics

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Engaging critics Preaching to converted

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Engaging critics Preaching to converted

Adapting to course of debate

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Engaging critics Preaching to converted

Repeating discredited claims

Adapting to course of debate

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Engaging critics Preaching to converted

Repeating discredited claims

Adapting to course of debate

legit minority opinion“maverick”

Crafting cohesive alternative theories

Nitpicking - scoring rhetorical points

Considering Totality of evidence

Cherry-picking & anomaly-hunting

Engaging critics Preaching to converted

Repeating discredited claims

Adapting to course of debate

“crank”legit minority opinion“maverick”

Justify ‘crank’ position

Your science ain’t perfect; consensus has failed in the past

Looser standards for evidence

There’s a conspiracy!

As a skeptic, when talking about weird things

Steer towards empirical and testable claims

Don’t use a paternalistic or mocking tone

Explore mundane explanations

Bring science into the discussion

Ask questions and listen carefully

Finally

Modern Skepticism isn’t a set of beliefs

It’s about avoiding faulty reasoning

It’s about recognizing and compensating for bias

It’s about respecting good evidence

Thank You!