Concrescence The Australasian Journal of ProcessThought

Whitehead: Relativity and Experience

Ronny DesmetCentre for Logic and Philosophy of Science,

Brussels University, Belgium

ronald.desmet@vub.ac.be

Alfred North Whitehead (18611947) is well-known forhis Principia Mathematica collaboration with BertrandRussell, and also for his later speculative adventures,especially as set forth in Process and Reality. However,this paper does not focus on the mathematics of hisCambridge epoch (18801910), nor on the metaphysicshe created after moving to the United States (19241947).We put here on the hot seat Whiteheads philosophyof science, which is associated with the intermediateperiod of his professional life in London (19101924).Next to the impact of the idealism-realism debate ofthe day, animating the London Aristotelian Society ofwhich Whitehead was an active member as of 1915, it isabove all else the British reception of Albert Einsteinstheories in the second decade of the twentieth centurythat has played a decisive role in the London periodof Whiteheads life. A main result was Whiteheadsnon-Einsteinian interpretation of Einsteins generaltheory of relativity, for which he forcibly argues in ThePrinciple of Relativity (1922). From the perspective of itsmathematical formulae and experimental consequences,Whiteheads alternative theory of gravitation is almostidentical with Einsteins original theory. However,its importance lies in the interpretative divergences,which enable us to draw a number of importantlessons, for example, on the difference betweenapplied mathematics and mathematical physics, on thedialogue (or lack of dialogue) between adherents ofdiverging paradigms, and on the competition betweenphilosophical interpretation and scientific success.

The lesson I want to highlight in this paper concernsthe relation between theory and experience. It is a

commonplace that a theory only receives the scientificlabel after being put on trial, i.e., after being checkedagainst our experience. However, which criteriaempirical research has to satisfy in order to be adequateremains an open question. A partial answer is offeredby the history of science. A theory sells itself (soto speak) in the first place by its prediction of anumber of crucial experimental observations. Thegeneral theory of relativity is a case in point. Oneof its most important sales arguments was Einsteinsprediction concerning light originating from stars. Ifthe starry sky is photographed twice, once by night,and once during a solar eclipse, all other things beingequal, then, upon comparison, we will observe exactlycalculated shifts of starlight spots near the solar coronaimprint. The pictures taken by English astronomerswith reference to the solar eclipse on May 29, 1919,seemed to confirm Einsteins prediction, and they wereone of the major factors which caused an instant successfor Einstein and his general theory of relativityatleast, after the observational results were made publicby Arthur Eddington on November 6, 1919, at a jointmeeting of the Royal Society and the Royal AstronomicalSociety. Whitehead was present at this meeting, and inan account published in Science and the Modern World,he wrote:

The whole atmosphere of tense interest was exactly thatof the Greek drama: we were the chorus commentingon the decree of destiny as disclosed in the developmentof a supreme incident. There was dramatic quality inthe very staging:the traditional ceremonial, and in thebackground the picture of Newton to remind us that thegreatest of scientific generalizations was now, after more

Concrescence, 2009, vol. 10: pp. 39. ISSN: 14454297 2009 The AuthorPublished online by the Australasian Association for Process Thought, an affiliate of the International Process Network.

mailto:ronald.desmet@vub.ac.behttp://concrescence.org/

4 Ronny Desmet

than two centuries, to receive its firstmodification. Norwasthe personal interest wanting: a great adventure of thoughthad at length come safe to shore. [?, 10]

For Einstein, and for most physicists and philosophers,testing a theory by means of a number of relevantexperiments is fully adequate. Not so for Whitehead.The experimental test is indeed the ultimate arbiter inthe game of science, but it cannot be the only one. Theinterface with experimental experience is too narrow,and needs to be broadened. Whitehead demands that thecommon ground between theory and experience is notonly fertilized by the creation of experimental facts, butalso by the coherence with ordinary sense experience.Whitehead writes:

There are two gauges through which every theory mustpass. There is the broad gauge which tests its consonancewith the general character of our direct experience, andthere is the narrow gauge [of experiment] which is . . . thehabitual working gauge of science . . .The evidence istwo-fold, and is fatally weakened if the two parts aredisjoined. [?, 34]

Whiteheads additional demand is an expression of hisprotest against physicists and philosophers who promotethe bifurcation of nature in a scientific world of highermathematics, and a common sense world of ordinaryexperience, the first, of course, being the real world,and the second, nothing more than an obstinate illusion.However, what does Whitehead mean with ordinarysense experience? And how can a scientific theory becoherent with it?

Whiteheads analysis of sense experience stems fromthe idea that our experience is a stream of experientialmoments in which each moment is initially determinedby its past. Each perceptual moment of experience isa synthesis of many, initially vague feelings of all pastthings which exercise a causal influence on this presentmoment, a synthesis which is further characterized bya process of clarification and of symbolic reference.This point of departure is at odds with the point ofdeparture taken by David Hume and Immanuel Kant.These philosophers start with the clear feelings whichRussell later called sense data. They hold our senseexperience to be a synthesis of colors, odors, tastes,and so on, into spatial and causal objects, a synthesischaracterized by habit (Hume) or conceptual activity(Kant). Whitehead does not deny that sense data playan important role in our sensory experience, but he

rejects that they are initially given. Whitehead warnsus for the fallacy of misplaced concreteness, whichtakes abstractions as more concrete than the realityfrom which they were abstracted. For him, the spatialpresentation of sense data is the immediate result ofan internal abstraction-process, which starts with realcausal influences, and ends with symbolic reference inwhich clear feelings usually refer to causal feelings.

Whitehead distinguishes three modes of perception ineach of our perceptual moments of experience: the puremodes of causal efficacy and presentational immediacy,and the mixed mode of symbolic reference. It ishard to illustrate these three modes. Usually, we areonly conscious of the latter mode, especially in thecase of visual experience. I open my eyes, and I seemy garden, the description of which would require anovel. Amultiplicity of causal influences originates frommy environment, including my body, and constitutesan immense influx, which, however, is immediatelyintegrated into an accomplished perceptual momentof experience. Hence, Im not aware that the influxinvolves my eyes, my nerves, and my brain, and yet, theevents immediately preceding the perceptual momentof experience are of utmost importance. Whiteheademphasizes

. . . that the predominant basis of perception is perceptionof the various bodily organs, as passing their experiencesby channels of transmission and of enhancement . . .Thehuman body is to be conceived as a complex amplifiertouse the language of the technology of electromagnetism. [?,119]

But if we forget that there is no sense experience withoutsense organs, the overly hasty conclusion reads that thebasis of our visual experience of the garden is nothingmore than the immediate show of patches of color in aspace-theater, which we ourselves turn into a garden. Inthe latter case, sense perception is unjustly reduced topresentational immediacy, and the door is left wide openfor all kinds of skepticism and idealism to enter. That iswhy an example of tactile experience is more appropriateto illustrate Whiteheads realistic vision, for when wetouch something, we always also feel our own skin, evenif the other bodily influences remain unconscious.

I open my front door, and a joker throws a bucket ofwater at me. Caught by surprise, I have not seen whathappened, and initially only feel the painful impact. At

Whitehead: Relativity and Experience 5

that moment, causal efficacy is dominant. Then I feelthat my face is wet. Now presentational immediacybecomes dominant, because the spatial presentationof wetness is being formed. And finally I concludethat water hit my face. The clear feeling of wetnessbecomes a symbol referring to the causal feeling ofimpact. In other words, symbolic reference becomesdominant. To avoid misunderstanding: all three modesof perception play their role in each moment of theperceptual stream of experience, and in this sense theexample is misleading. However, it does clearly showthat with symbolic reference the possibility of error isintroduced. I cannot doubt my direct feelings, such asthe painful impact and the wetness I feel, but how certaincan I be that it is not wine instead of water that hit myface? Further perception might resolve the issue. Forexample, by smelling, or by licking my lips, I can test myconjecture that water is involved, and not another liquid.

The possibility of wrong symbolic reference is notpurely negative. In Symbolism: Its Meaning and Effect,Whitehead writes:

We all know Aesops fable of the dog who dropped a pieceof meat to grasp at its reflection in the water. We mustnot, however, judge too severely of error. In the initialstages of mental progress, error in symbolic reference is thediscipline which produces imaginative freedom. Aesopsdog lost his meat, but he gained a step on the road towardsa free imagination. [?, 19]

And in Process and Reality, Whitehead repeats:When human experience is in question, perception almostalways means perception in the mixed mode of symbolicreference. Thus, in general, human perception is subject toerror, because, in respect to those components most clearlyin consciousness, it is interpretative. In fact, error is themark of the higher organisms. [?, 168] In sense-perceptionwe have passed the Rubicon, dividing direct perceptionfrom the higher forms of mentality, which play with errorand thus found intellectual empires. [?, 113]

Hence, we might add thatironicallyscience, ourcontemporary detector and corrector of erroneous senseperceptions, originated from the possibility of errorin symbolic reference, as all products of the freeimagination do.

Some further examples of wrong symbolic referencebring us closer to Whiteheads notion of passing thebroad gauge, in other words, closer to what it means fora scientific theory to be coherent with ordinary sense

experience. If I do not notice that the rear wall of theshop I entered is amirror wall, thenmy visual experiencerefers to continuing shelves, whereas the shelves end atthe rear wall. Further experience, in the worst case bybumping against the mirror, can correct this mistake. Ifa patient feels his or her amputated left hand, this is aclear case of mistaken reference. One look is sufficientevidence. If I see the sun go down, my experiencerefers to a flat earth. Satellite pictures illustrate that thisreference is erroneous. I also consider the sun I seeat present as simultaneous with my experience, but if Itake into account the science of my distance to the sun,and of the finite speed of light, I realize my mistake.Should the sun disappear at once, I would observe thisdisappearance no sooner than eight minutes later.

This sequence of examples allows us to draw someconclusions. First, wrong symbolic reference does notrender our direct feelings invalid or unreal. Not even inthe case of phantompain.The pain is real, but the patientis mistaken about the cause. Whitehead writes:

The word delusive is all very well as a technical term;but it must not be misconstrued to mean that what wehave directly perceived, we have not directly perceived.Our direct perception . . . remains an ultimate fact. Ourinferences are at fault. [?, 64]

Secondly, science can reveal the true causes of our directfeelings. A human person is not a dog barking alllife long at his or her mirror image, and the laws ofoptics can help him or her to have the perceived mirrorimage refer more exactly to what happens in front of themirror. The neurologist has a hypothetical explanationof phantom feelings. The unconscious process in thecerebral cortex, which processes bodily signals, did notyet fully adapt to the reality of the left hand amputation.Cerebral tissue aches for sensorial input, and hence,signals from nearby cerebral regions, which originatedin other bodily parts, are attracted by the region that wascausally effective as processor of the left hand stimuliprior to the amputation. Thats why the slightest touchof the patients left cheek can cause a sensation ofthe amputated left thumb. Thirdly, and finally, theseexamples prove that a scientific theory does not haveto be at odds with ordinary sense experience. Theoptician can explain perfectly why we see the mirrorimage the way we do, the astronomerfor example, bymeans of a scale modelwhy we see the sunset the

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way we do. As a matter of speech, wrong symbolicreference is a consequence of myopia. A more inclusiveview on the world is possible; a scientific view enablingto explain our ordinary sense experience, including itswrong references.

The latter is Whiteheads answer to the question of howa scientific theory can be coherent with our ordinarysense experience. With his requirement of coherence,Whitehead does not claim that our scientific worldviewmust never contradict and correct our common senseworldview. A spherical earth is not flat. The sun nowis not the sun eight minutes ago. But Whitehead doesclaim that our ordinary sense experience needs to receiveits due place in our scientific worldview, even whensense perceptions are involved, which amount to wrongsymbolic references. To include the sun of eight minutesago in my present perceptual moment of experience, asif it is simultaneous with this moment, may be wrong,but it is a perfectly explainable error, and the finitude ofthe speed of light prohibits our organism, and even ourmost sophisticated equipment, to obtain amore accurateperception from earth.

The original source of inspiration of Whiteheadsphilosophy of science was James Clerk Maxwells theoryof electromagnetism. In Maxwells theory the spatialspread of charge is coupled to the causal flux ofelectromagnetic events. Expressed a bit more technical:Maxwells theory is characterized by the mathematicalcoupling of the scalar field of charge to the evolutionin time of the electromagnetic vector field. Scalar fieldand vector field are both abstractions of which theinterplay constitutes the theory of electromagnetism.Compare Whiteheads analysis of sense experience withMaxwells analysis of electromagnetism, namely, thespatial presentation of sense data with the scalar fieldof charge, the causal feelings with the electromagneticvectors, and the symbolic reference (from presentationalimmediacy to causal efficacy) with the mathematicalexpressions relating scalar field and vector field. Thesimilarity is no coincidence. Whitehead requires andengineers similarity, consonance, and coherence.

In all his writings, Whitehead remains faithful to hisearly Maxwellian inspiration. For example, whenspeculatively generalizing his analysis of a perceptualmoment of experience to any moment of experience inProcess and Reality, Whitehead still takes recourse to the

language of the theory of electromagnetism. Dealingwith the generalization of perception in the mode ofcausal efficacy, Whitehead writes:

In the phraseology of physics, this primitive experience isvector feeling, that is to say, feeling from a beyond whichis determined and pointing to a beyond which is to bedetermined. [?, 163] In the phraseology of mathematicalphysics a [causal] feeling has a vector character. [?, 231] Ina [causal] feeling there is a vector character which transfersthe cause into the effect. [?, 237]

Dealing with the generalization of perception in themode of presentational immediacy, Whitehead writes:

In the language of physical science, the scalar formoverwhelms the original vector form: the origins becomesubordinate to the individual experience. The vector formis not lost, but is submerged as the foundation of the scalarsuperstructure. [?, 212]

It is Whiteheads aim to make sure that his analysisof ordinary sense experience, as well as his latermetaphysical analysis of all experiential moments theworld consists of, agree with the general principlesaccording to which the notions of modern physics areframed. [?, 116]

According to Whitehead, each new scientific theoryconstitutes a challenge for our ordinary sense experience.But he holds the reverse to be true as well: eachanalysis of our ordinary sense experience challengesthe natural sciences. Indeed, according to Whitehead,ultimately, the scientific vector-adventures of scalars(charges, masses, etc.) should be able to explain theordinary instances of sense perception of objects. IfI add that the concept of tensor is a generalizationof the concept of vector, nobody will be surprised tolearn that Whiteheads alternative theory of gravitationis an electromagnetism-like theory, in which thetensor-adventures of masses are coherent with theanalysis of our ordinary sense experience in terms ofWhiteheads three modes of perception.

Whitehead emphasizes, again and again, that a theoryof natural science must be coherent with the uniformityrequired and exhibited by the spatial presentation ofsense data in presentational immediacy, and by thesymbolic reference of this immediate presentation tothe causal efficacy. Many complex pages of Whiteheadsoeuvre aim to show that the required coherence with theuniformity which is essential for our sense experience,

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can only be realized if the scalar, vector, and tensor fieldsof physics are defined in terms of a uniform space-timegeometry. Whitehead writes:

It is inherent in my theory to maintain the old divisionbetween physics and geometry. Physics is the science of thecontingent relations of nature and geometry expresses itsuniform relatedness. [?, vvi]

As Einsteins general theory of relativity does not satisfythis requirement, according to Whitehead, it is marredwith a lack of coherence with our ordinary senseexperience. And he writes

. . . that our experience requires and exhibits a basis ofuniformity, and that in the case of nature this basis exhibitsitself as the uniformity of spatio-temporal relations. Thisconclusion entirely cuts away the casual heterogeneity ofthese relations which is the essential of Einsteins . . . theory.[?, v]

Here, I drop the complexity of Whiteheads account inan attempt to illustrate this lack of coherence with anexample in which firstWhiteheads interpretation will bediscussed, and then Einsteins interpretation.

Our point of departure is the comparison of twopictures of the starry heaven I evoked earlier. The firstpicture is taken at night, the second one during a solareclipse (all other things being equal). The comparison(supported by measurement, but I leave that aside)entails the observation that a number of starlight spotsnear the solar corona imprint have shifted (relative tothe non-shifted starlight spots further away from thecorona). Whitehead interprets these shifts as causedby the bending of starlight when passing near the sun,and his scientific interpretation is coherent with ourordinary sense experience. The moment I see the firstpicture, this two-dimensional spatial presentation ofstarlight spots is immediately, and largely unconsciously,being processed into a three-dimensional presentation(presentational immediacy) of stars instead of spots(symbolic reference). To go short: I immediately see astarry heaven. The same holds for my visual experienceof the second picture. However, when I compare mysecond experience with my first, I notice that a numberof starts have assumed another position in the starryheaven. Since I know that the position of faraway starscannot depend on a contingent eclipse in our solarsystem, I conclude that my second visual experience ismarred by incorrect symbolic reference. As in the case of

the spontaneous mistake of referring the mirror imageof a real star to a virtual star that emits its light to me ina straight line from behind the mirror, I wrongly referthe photographic image of a real star to a virtual starthat emits its light to me in a straight line passing theeclipsed sun. Whiteheads interpretation that starlightis bent when passing near the sun is coherent with ourordinary sense experience, and it allows me to detectand correct my incorrect symbolic reference. This canbe visualized by means of the following figure (Fig. 1),which pictures both the error, and its correction, boththe virtual star P with its rays of light PFE that are notbent by the sun S, and the real star P with its rays of lightPQFE that are bent by S.

Figure 1.

This figure dates from 1920, and is taken from [?].

Eddington, however, discusses Einsteins theory, notWhiteheads. But, if Eddington, and in his trail, mostauthors expounding the general theory of relativity,interpret the experimental observations during thefamous 1919 solar eclipse the way Whitehead does, canwe still hold that a difference exists betweenWhiteheadsinterpretation and Einsteins? Can we still hold thatEinsteins theory does not coherewith our ordinary senseexperience? According to Whitehead, we can indeed.True, Einsteins predictions of the shifts we observe whencomparing the two pictures of the starry heaven alsofollow from a comparison of the star light paths by night,and during the solar eclipse, but in his theory these pathsare exactly calculated geodesics (maximal straight lines)in a variably curved space-time, where the curvatureis determined (among other things) by the mass ofthe heavenly bodies which are present. Abstractingfrom time, and from the effect of heavenly bodies ontime, we can say that the space in between earth andphotographed starry heaven is less curved by night thanduring the daytime, during the solar eclipse, because inthe first case the sun is not present, but in the second caseit is. Furthermore, light travels as straight as possible.Consequently, the starlight will follow a geodesic path by

8 Ronny Desmet

night in a less curved space than by day. And since thenightly three-dimensional region and the solar eclipsedthree-dimensional region are differently curved, insteadof equally or not curved, we cannot visually comparethem, not with the help of Eddingtons Fig. 16, and noteven with a three-dimensional model.

In Einsteins interpretation the curvature of spaceis variable, the nature of space depends upon thecontingent presence of heavenly objects. Consequently,our knowledge can no longer rely on our ordinary senseexperience, and meaning can no longer be based onour ordinary symbolic reference. Whitehead writesthat in philosophy in general the failure to lay dueemphasis on symbolic reference . . .has reduced thenotion of meaning to a mystery. [?, 168] In linewith this aphorism, focusing on Einsteins interpretation,Whitehead writes:

I cannot understand what meaning can be assigned tothe distance of the sun from Sirius if the very nature ofspace depends upon casual intervening objects which weknow nothing about. Unless we start with some knowledgeof a systematically related structure of space-time we aredependent upon the contingent relations of bodies whichwe have not examined and cannot prejudge. [?, 5859]

Notice that this does not imply that we can no longercompare the two pictures of the starry heaven. Thisexperimental observation is still reliable according toEinsteins theory, because both pictures register thelocal impact of starlight, and locally, Einsteins variablycurved space-time is an identical twin of the uniformspace and time required and exhibited by our ordinarysense experience. So, even though Eddingtons crucialexperiment (like all experiments) still invokes ourordinary sense experience, it remains a valid experimentin Einsteins interpretation. The issue is not a local one,but a global one. Becausewewant to picture the situationglobally, conform our ordinary sense experience, andhence, because we want to picture the starry heaven,via presentational immediacy and symbolic reference,against the background of a uniform space, a usuallyunnoticed problem of incoherence arises. Einsteinsinterpretation is at odds with the visual representationby means of which Eddington, and Einstein himself,spontaneously interpreted this 1919 experiment. Early in1920, Whitehead writes:

The detailed deductions [of Einsteins general theory ofrelativity] are important, because unless our colleagues

the astronomers and the physicists find these predictionsto be verified we can neglect the theory altogether. Butwe may now take it as granted that in many strikingparticulars these deductions have been found to be inagreement with observation. Accordingly the theory hasto be taken seriously and we are anxious to know what willbe the consequences of its final acceptance. Furthermoreduring the last few weeks the scientific journals and thelay press have been filled with articles as to the nature ofthe crucial experiments which have been made and as tosome of the more striking expressions of the outcome ofthe new theory. Space caught bending appeared on thenews-sheet of a well-known evening paper. This renderingis a terse but not inapt translation of Einsteins own way ofinterpreting his results. I should say at once that I am aheretic as to this explanation and that I shall expound to youanother explanation based upon some work of my own, anexplanation which seems to me to be more in accordancewith our scientific ideas and with the whole body of factswhich have to be explained. [?, 5859]

Together with Einstein we might say: forget thewhole body of facts, it is sufficient that the theory ofrelativity conformswith the facts created by our scientificexperiments. Our ordinary sense experience, in general,does not correspond with reality, but fortunately it doesin the particular circumstances of our survival, andalso of our scientific experiments. For our daily life,the wrong symbolic references of our sense experienceare usually not harmful, but for our scientific life, theyare, and have to be replaced by the more trustworthysymbolic references of our mathematics. Einsteinthesame man who unified space and time, as well asmass and energy, in the special theory of relativity, andwho then unified space-time geometry and gravitationalphysics in the general theory of relativitysplits ourworld in two: we live in two separate worlds, thecommon senseworld of our ordinary experience, and thescientific world of our higher mathematics.

Whitehead decisively rejects this bifurcation of nature.For him, Einsteins lack of coherence must be remedied.For him, experimental success is not sufficient, and thetheory of relativity must be made to cohere with ourordinary sense experience. For Whitehead, the fact thatEinstein neglects the spatio-temporal uniformity that isrequired and exhibited by our ordinary sense experienceis a bridge too far. Whitehead holds:

In investigating the laws of nature what really concerns usis our own experiences and the uniformities which they

Whitehead: Relativity and Experience 9

exhibit, and the extreme generalities of the Einsteinmethodare only of value in so far as they suggest lines along whichthese experiencesmay be investigated. (Whitehead apud [?,193])

Fifty years after Whitehead, Ilya Prigogine, in line withWhiteheads vision, held that it is equally unacceptablethat Einstein degraded the temporal irreversibility tobeing an illusion, for the irreversibility of time isessential for our experience as well. Anyway, forWhitehead, ultimately, all symbolic references, whetherthey are linguistic or mathematical, must be based onthe symbolic reference that is proper to our perceptualexperience. All of Whiteheads philosophical writingscan be read as a philosophical analysis of our perceptualmoments of experienceand more generally: as aspeculative analysis of all experiential momentswhichintends to root each proposition, unconscious orconscious, linguistic ormathematical, in the reality of theexperiential moment.

In his philosophy of science, Whitehead limits

himself to a reinterpretation of Einsteins mathematicalpropositions until they are coherent with our ordinarysense experience. The general relational frameworkcreated in his philosophy of science, however, issufficiently broad to accommodate quantum mechanicsas well, and to guarantee the consonance of (a variantof) Niels Bohrs interpretation of quantum mechanicswith the character of our ordinary sense experience.Here, I cannot deal with the latter claim, but instead oftaking Whiteheads philosophy of science as the workof a reactionary who could not digest Einsteins ideaof a variably curved space-time, this claim supportsmy belief that it is better to conceive of his work as aninvitation to reconsider the relation between science andexperience. In any case, Whitehead writes, languageand algebra seem to exemplify more fundamental typesof symbolism than do the Cathedrals of MedievalEurope. But, he adds: There is [a] symbolism morefundamental than any of the foregoing types. [?, 2] Andwith this latter phrase, Whitehead does indeed aim atthe symbolism of our ordinary sense experience.