‘… a sort of composite photograph’: Pragmatism, Ideas, and Schematism.

by Christopher Hookway

1. Introduction

Around 1898, Peirce wrote that an idea ‘can be roughly compared to a composite photograph’. (CP 7.498) [1] A few years later, he urged that the predicate “yellow” refers to ‘a sort of composite photograph of all the yellows I have seen.’ (CP 7.634) Indeed, a predicate expression ‘only conveys its signification by exciting in the mind some image, or, as it were, a composite photograph of images.’ (CP 2.317) This metaphor is employed on many occasions – I have found many instances dating from 1893 (CP 2.435ff) until 1908. Moreover it is not applied only to simple sensory ideas such yellow: Peirce’s own examples include moral ideals, and he went so far as to claim that all the operations of the intellect consist in taking ‘composite photographs of quale consciousness’. (CP 6.233)

This metaphor, that an idea is a sort composite photograph, seems to have been very important to Peirce: he employed it on many occasions over a period of at least fifteen years; and there is no evidence that he was ever dissatisfied with it. It is reasonable to conclude that he found it useful for capturing some important features of cognition. This makes it surprising that it has received little scholarly attention. [2] What makes the metaphor so suggestive? To what features of cognition does it draw our attention? Although I do not pretend to give the final word on this topics, this paper makes a start on formulating the issues they raise and explaining why they are important for understanding Peirce’s thought.

The concept of a composite photograph may be less familiar now than it was in the late nineteenth century. It is striking that although Peirce uses it on many occasions, he never sees any need to explain just what it means. Section two explains the concept of a composite photograph, one that had wide currency in scientific circles at the time at which Peirce was writing. We then examine a selection of the passages in which Peirce uses the concept in order to explain the nagture of how general terms and concepts function (section three).

This prepares for a discussion of the role of the concept in Peirce’s defense of his pragmatism (section four) and some of its connections with an important aspect of what Peirce learned from Kant (section five). The concluding section offers a conjecture of just what the force of this metaphor or analogy was. This will enable us to identify some features that composite photographs must possess if they are to meet Peirce’s philosophical needs. We can then turn to some crucial interpretative issues. What does Peirce hope to gain from the claim that ideas are photographs? What additional insight is promised by the claim that they are composite photographs? And just what does it mean to say that an idea is ‘composite’ in this way?

One reason that this issue is interesting is that it has a bearing on Peirce’s search for a proof of pragmatism that preoccupied him in the first decade of the twentieth century. I suspect that the appeal of the metaphor depended on the fact that it captured something that was central to pragmatism: if the metaphor can indeed be made good, then the shape of the proof of pragmatism may become much clearer. Richard Robin once commented that Peirce’s search for a proof ‘is neither inductive nor deductive. Nor is it transcendental. Rather it has that special character related to a coherentist defence, which in itself is a reflection of an underlying architectonic conception of philosophy’. [3] This seems right. As Robin records, it is easier to assemble the many elements of Peirce’s philosophy that were relevant to the proof than to fit all the pieces together. It is characteristic of such a ‘coherentist’ defence that we need metaphors to keep a grip on the whole while assembling the parts and attempting to find the detailed ways in which they should be connected. The metaphors are especially valuable when they reflect the traces of other large philosophical systems, enabling us to identify tasks that arise within other systems of philosophical architectonic whose inspiration we wish to acknowledge but whose details, we think, involve mistaken conceptions. The metaphor of a composite photograph, I shall suggest, serves these two roles. It makes vivid some of the requirements for an adequate defence of pragmatism, and it enables Peirce to acknowledge some links between his system of architectonic and Kant’s.

2. Composite photographs

The Century Dictionary provides a very clear definition of ‘composite photograph’:

A single photographic portrait produced from more than one subject. The negatives from the individuals who are to enter faces are made as to show the faces as nearly as possible of the same size and lighting and in the same position. These negatives are then printed so as to register together upon the same piece of paper, each being exposed to the light for the same fraction of the full time required for printing. It is believed that by study and comparison of such photographs made from large series of subjects, types of countenance, local, general, etc can be obtained. (1152)

The technique is most commonly associated with the statistician and eugenicist Francis Galton, who produced composite photographs to display the common characteristics of criminals and of members of learned organizations. According to an article by Joseph Jastrow in Science, the process was employed to find a solution to two problems. First: ‘Given a series of objects having in common an interesting characteristic, to find a single type which will represent the whole group.’ (p.165) And second: ‘given a series of representations of the same object, to find a single representation which shall give a superior effect by combining the strong points and neglecting the defects, of each of the series.’ The second case is illustrated by considering ‘the composite of six medallion heads of Alexander the Great’, which ‘might be taken to represent the real Alexander better than any one of the originals, because the probability of the six artists having introduced the same inaccuracy is very small’. When we address the first problem, however, ‘we are introducing an essentially new face, - a type representing par excellence the peculiar characteristic for which the originals were grouped together.’ Using examples that reflect Galton’s innovative work, he points out that ‘In combining the portraits of criminals, the object is get a type of criminality; in combining the portraits of national academicians, one of recognized scientific ability.’ [4]

The fact that Jastrow wrote this 1885 article means that there can be no doubt of Peirce’s familiarity with the techniques described. Jastrow attended Peirce’s logic classes at Johns Hopkins in 1882-3 (W4: lv), claiming that they gave him his ‘first real experience of intellectual muscle’. (W4: xliii) The classic paper they wrote together, ‘On small differences in sensation’ (W5: 122-35) appeared in 1885, the same year (and in the same journal) as Jastrow’s paper on composite photography. Moreover when Peirce delivered an early draft of their joint paper at meetings of the National Academy of Sciences in October 1884, he also participated in discussions of a paper ‘On an

experimental composite photograph of the members of the academy’. [5] (W4: xxxv) There can be no doubt of what Peirce had in mind when he wrote of ‘composite photographs’ a decade later.

A composite photograph promises to provide a sort of stereotype: a single representation that somehow captures the common features of all the particular ones. A contemporary example helps to make this clear. The photographer Nancy Burson attempted to capture the differences in ideals of female beauty characteristic of the 1950s and 1980s. Her ‘First Beauty Composite’ combined Bette Davis, Audrey Hepburn, Grace Kelly, Sophia Loren and Marilyn Monroe; and the representation of beauty from the 1980s composed Jane Fonda, Jacqueline Bisset, Diane Keaton, Brooke Shields, and Meryl Streep. [6] As Terry Landau notes, the results do seem to ‘capture and epitomize the differences in the ideal of the 1950s and of the 1980s’: registering, for example, ‘the arched eyebrows and heavily made up mouth of the fifties beauty versus the more “generic” natural look of the eighties’. [7] Of course the results will be influenced heavily by the choice of subjects and by the means by which the photographs are combined: once an artist such as Burson uses a computer rather than the simple photographic techniques advocated by Galton and his followers, there is no temptation to regard the results as an innocent combination of effects of light on lens and film. There probably never was any such temptation. Jastrow was clearly aware of how results are affected by just how the different faces are lined up, and observed that features from male photographs tended to dominate in composites of subjects of different sexes. The prevalence of facial hair and differences in dress were contributing factors, he suggested. (166)

It is not surprising that the most interesting examples of composite photographs involve faces: if I try to combine photographs of every house I have every seen, or every mammal, it is hard to see why anything interesting or revealing should result. Most likely we would find simply a formless and undifferentiated mess. So the suggestion that composite photographs could be found that correspond to all our ideas cannot be taken seriously. Galton himself was aware of this. As he admitted in his book Inquiries into Human Faculty [8] , his attempts to construct ‘really representative faces of ‘the criminal type’ were unsuccessful. While the results displayed someone ‘of mean description’ it did not capture the essence of ‘villainy’. They resembled many non-criminals more closely than they resembled many or most criminals; they had ‘no villainy written on them’. Galton himself seems to have concluded that there may be different types of villainy, his disappointing results thus being attributed to the fact that he tried to find a common factor to all these different types. His editor, Karl Pearson, urged, surely more plausibly, that villainy is a mental

characteristic which need not be associated with any particular physical features, and hence would not show up in photographs. It seems to be agreed that illuminating composite photographs will be found for only a limited range of ideas. [9]

We must distinguish the claim that an illuminating composite photograph can be constructed for some idea from the thesis that our possession of such ideas or concepts can be explained by saying that we possess appropriate ‘composite photographs’ – more strictly that we possess things that are strongly analogous to composite photographs. Perhaps we use composite photographs as a ‘template’ or stereotype in applying concepts – or in applying at least some concepts. Perhaps we recognize people or types by comparing them with a stored schema or template, with a stored ‘composite’. How this could work may be mysterious, but the quotations from Peirce suggest just such a view. Moreover, we should note that Jastrow is most famous in contemporary philosophy as the originator of the duck-rabbit ambiguous figure. Perhaps we turn the duck into a rabbit figure by bringing to bear an appropriate visual template, our rabbit composite taking the place of our duck one. If we need such templates or schemata to explain our use of concepts that are applied to things on the basis of how they look, and if we think that they must be the results of our earlier experiences of ducks and rabbits, then perhaps the composite photograph analogy has some explanatory value. It might explain how we can see something as a rabbit. Even in cases like rabbit, we would surely need a set of templates which would enable us to recognize rabbits from different directions, when engaged in different kinds of behaviour and so on. And Galton’s suggestion that we may need different composites that apply to different cases – to different kinds of ducks, for example – may also have to be endorsed. This paper is concerned with passages in which Peirce appears to endorse this strong thesis.

3. The Short Logic: composite photographs and general terms

Armed with an understanding of what composite photographs are, we can turn to the passages in which Peirce uses the notion. We begin with the earliest use of the metaphor with which I am familiar, a discussion in the Short Logic of around 1895 (see CP 2.435-441; also in EP2: chapter 3). Peirce has just explained the central ideas of his theory of signs and introduced one of his most important classifications of signs. This distinguishes symbols from indexical signs and icons, and he is returning to his familiar claim that an adequate language for expressing thoughts must employ signs of all three kinds. The section

we are concerned with was subtitled ‘Judgments’ – it is concerned with the content of judgments and assertions. A judgment or assertion is an act, and Peirce tells us that it always involves the judgment or assertion that ‘two different signs have the same object’ (CP 2.437, EP2: 20). I ‘cause an image or icon to be associated … with the object represented to us by an index.’ When I see someone and judge them to be a rascal, I use an index (perhaps a demonstrative or a name) to pick the person out, and I apply a general idea or concept to them. For the assertion to be true, the person picked out by my indexical sign must be identical to one of the objects of the concept of a rascal. As we have seen, Peirce holds that the general concept (rascal in this case) takes the form of an ‘image or an icon’.

Other examples exhibit the same pattern. Even if I say ‘It rains’, which does not appear to involve demonstrative reference, the concept of raining is applied to an indexically identified time (and, presumably, a place): the rain is predicated of now and here. (CP 2.438, EP2: 20) In fact things are more complex than these examples allow: most propositions will involve a set of indices, and the iconic representation will apply to that set.

Thus in the proposition, “A sells B to C for the price D,” A, B, C, D form a set of four indices. The symbol “- sells – to – for the price –” forms a mental icon or idea of the act of sale, and declares that this image represents the set A, B, C, D, considered as attached to that icon, A as seller, C as buyer, B as object sold, and D as price. If we call A, B, C, D four subjects of the proposition and “- sells – to – for the price – ” a predicate, we represent the logical relation well enough, but we abandon the Aryan syntax. (CP 2.439, EP2: 20-21)

Subsequent sections consider more complex propositions and inferences in ways that need not concern us here. It is enough to see that Peirce is drawing a logical distinction between the roles of indexical expressions that identify the ‘subjects’ of propositions and the rather different ‘iconic’ role of predicative expressions.

Within this short passage, he uses the ‘composite photograph’ metaphor several times in explaining the iconic role of the predicative component of propositions. When I apply the concept of dishonesty to someone, ‘I have in mind something like a “composite photograph” of all the persons I have known and read of who have had that character’ (CP 2.435, EP2: 19-20). In the case of “it rains”, ‘the icon is the mental composite photograph of all the rainy days the thinker has experienced.’ (CP2.438. EP2: 20) [10] So the appeal to composite photographs is intended to illuminate the character of what we can call the predicative component of a thought or proposition. That the idea

reflects ‘all people I have known or read about ..’, or ‘all the rainy days the thinker has experienced’ indicates that an explanation is offered of how such ideas can be general, applicable to a wide range of cases, including those that have not previously been encountered. And the description of it as a ‘photograph’ is, perhaps, intended to help us to understand how such signs can be iconic. But the passages considered here offer little insight into how such representations work, of just how our ideas are both general and iconic.

One clarification should be made here. Peirce claims that the predicative expressions employed in a public language function as (conventional) iconic signs. He also claims that mental representations of general conceptions employed (ideas) function iconically. I have already discussed the former on a number of occasions. [11] The composite-photograph metaphor is used to describe ideas (mental representations); it is not applied directly in characterising the iconic form of words from public language. Indeed, as we have seen, Peirce often suggests that public language predicates serve as conventional public symbols of ideas.

The examples we have considered remind us of another feature of Peirce’s position. The ideas are composites of those rainy days that the thinker has experienced, of those dishonest people that he has known or read about. Hence the metaphor seems to tell us something about the history or genesis of our ideas. The idea is ‘composed’ of cases with which the possessor the idea has been in sensory content. This echoes the empiricist conception that our ideas are produced by our sensory encounters with the world. Indeed, we may be struck by the analogies between Peirce’s talk of composite photographs and Locke’s claims about abstract ideas: we obtain the latter when by eliminating all that is not common to all ideas of (say) a rascal; we obtain the former by compounding photographs so that what is most commonly found in cases we have encountered becomes predominant. We can now list some features of ideas that are to be explained by the metaphor:

a) Ideas are iconic signs or representations (which function as components of contents that can be judged).

b) Ideas are composed out of cases which the subject has known: has experienced, or of which knowledge has been obtained through testimony.

c) Ideas are general. The nature of our ideas must explain how they can be applied to new and unfamiliar cases.

One source of the mystery of Peirce’s claims here can now be expressed clearly. The metaphor holds that an idea is a composite photograph. What does composition consist in? If, as suggested in the previous section, many ideas cannot be associated with ordinary composite photographs, then his claim can have the evident plausibility he takes it to have only if other forms of ‘composition’ are allowed for. We also need to ask how general Peirce’s claim is supposed to be. If, as the passages suggest, it is to apply to all ideas, we have further reason to take this notion of composition metaphorically: what kind of composition is involved in my idea of rain, or of yellow, or of a rascal? Until we have answers to these questions, Peirce’s claims are wholly unclear.

Similar claims are found in later texts. We learn that a predicate expression ‘only fulfils its signification by exciting in the mind some image, or, as it were, a composite photograph of images’ (CP 2.317, c1902). When I wake and say ‘It is broad daylight’, my momentary experience is connected to ‘the composite photograph of daylight produced in my mind by all my similar experiences.’ (CP 3.621, from the Dictionary of Philosophy and Psychology). There is some interesting variety in the things that are identified with composite photographs. As well as ideas, we encounter: images (CP 2.441, 1893), and qualities, which are ‘composite photographs of ideas of feeling’ (CP 4.257, c1897). I shall not consider the significance of this variation. It is also useful to note a passage where Peirce applies the metaphor to ideas that are not primarily sensory: as well as mathematical examples, he suggests that a ‘moral ideal’ can be ‘a sort of composite photograph’ (CP 1.573, cross reference). So one question we confront is: what metaphorical force does the notion of a composite photograph carry once we consider cases where real composite photographs would be of no or little value? What insights can be conveyed by this wide application of the idea of a composite photograph?

4. Composite photographs and pragmatism

The passages we have considered so far do not suggest any close connection between the composite-photograph metaphor and Peirce’s pragmatism. I shall now note some passages in which these themes are linked and also suggest that the metaphor introduces some ideas which are central to Peirce’s search for a proof of his pragmatism. We begin with the latter.

In the seventh of the ‘Pragmatism’ lectures of 1903, Peirce identified three ‘cotary propositions’ upon which his demonstration that the pragmatist principle was the ‘whole logic of abduction’ depends. The first was:

‘Nihil est in intellectus quod non prius fuerit in sensu’.

He explained this further by saying that the starting point for all our ideas lies in sensory judgment. (CP 5.181, EP 2 226-7) The analogy between photographs and ideas – and the suggestion that all of our ideas can be understood as composed from ‘photographs’- captures this idea, even if it does little to explicate how sensory input should be understood. But more important, since composite photographs correspond to general ideas, the metaphor provides a story about how sensory input can give rise to general ideas: the relation of idea to sensory judgment is analogous to that between composite photograph and particular photograph. At least, so it appears.

Now the core of pragmatism is that the content of an idea can be clarified exhaustively in terms of the sensory judgments we should expect to make, if a variety of circumstances, including ones in which we act upon our surroundings. There is no part of the content of the idea which has a different source, coming perhaps from a priori intuition or from the a priori structure of our understanding. If an idea is a composite-photograph, then its content can be traced entirely to the ‘photographs’ from which it is composed. So if particular photographs are analogous to sensory judgments, and if the content of an idea is exhaustively clarified by describing how it is ‘constructed’ out of sensory judgments, then a ‘photograph’ which is composed entirely out of particular photographs will be (at least in this) analogous to an idea. What this shows is that if the metaphor can be shown to work for all our ideas, and if a suitable analogy can be found between the composition of photographs and the ‘construction’ of ideas, then some sort of argument for pragmatism may be forthcoming.

Before we continue, we should note the other two ‘cotary propositions.’ The second is:

… perceptual judgments contain general elements, so that universal propositions are deducible from them in the manner in which the logic of relations shows that particular propositions usually … allow universal propositions to be necessarily inferred from them. (EP 2: 227)

We saw that composite photographs are supposed to have a general character and that this follows from their being composed of a number of particular photographs. However if perceptual judgments correspond to the particular photographs from which the composite is made, then the metaphor seems to find no room for the claim that even perceptual judgments involve generality. Is this a weakness of the metaphor? No: according to Peirce, even particular photographs are ‘composite’: since the exposure is not instantaneous, the photograph is ‘composed’ out of a number of successive impacts of lights. (CP 2.442) So perhaps the metaphor helps us to see how perceptual judgments can share this feature of more abstract judgments. To differing degrees and in different ways, each corresponds to a photograph that is composite. However the similarities between these claims have limits: the relation of particular to composite photographs does not seem to be analogous to that between perceptual judgments and other propositions that can be inferred from them using the logic of relations. We shall return to this in the final section.

The third cotary proposition urges that generality is present in percpetual judgments because the latter are ‘nothing but the extremist case of Abductive judgment’. (EP2: 229). If that is correct, then the process by which generality enters perceptual judgments and the process by which general concepts are arrived at in reflective reasoning have a similar structure: each involves abduction, recognizing that some general conception makes sense of the available data. Perception then leaps to acceptance of this judgment unless reflection leads us to revise our perceptual belief, while more reflective inquiry takes the abduction as a suggestion which can be tested experimentally or reflectively before being accepted. This does not undermine the parallel between the cases. But, if the way we have related the use of the metaphor to the three cotary propositions which ground Peirce’s 1903 proof of pragmatism is correct, then we face another apparent difficulty. The passages from the Harvard Lectures suggest that experience yields general ideas – and perceptual judgments are formed – through a process of inference. Thus the construction of composite photographs out of particular photographs must be a metaphorical way of thinking about a process of inference. Fortunately, the texts bear this out. In this review of Pearson’s Grammar of Science Peirce discusses the example of seeing an inkstand.

He notes that ‘our logically initial data are percepts’ and, remarking that these involve three sorts of psychical elements, he continues:

… their qualities of feelings, their reactions against my will, and their generalising of associating element. But all that we find out afterward. I see an inkstand on the table: that is a percept. Moving my head, I get a different percept of the inkstand. It coalesces with the other. What I call the inkstand is a sort of generalized percept, a quasi inference from percepts, perhaps I might say a composite photograph of percepts. (CP 8.144, EP2: 62, 1901)

What does the allusion to composite photographs add to this?

One further passage in Peirce’s writings, from ‘Consequences of Common-Sensism’ explicitly relates composite photographs to pragmatism. If a critical common-sensist is also a pragmaticist, he writes:

He will further hold that everything in the substance of his beliefs can be represented in the schemata of his imagination; that is to say, in what may be compared to composite photographs of continuous series of modifications of images; these composites being accompanied by conditional resolutions as to conduct. (CP 5.517, c.1905)

This passage is important for two reasons. First we should register the Kantian tone: we are concerned with how beliefs (and ideas) are represented in the schemata of the imagination. It is these schemata that are compared to composite photographs. Perhaps we must look to Kant for further information about what composite photographs are supposed to do for us. And second, we learn more about the objects of these composite photographs. We noted earlier Peirce’s reference to photographs of ideas, qualities and images; now we find that they are of continuous series of modifications of images. Given Peirce’s synechism, this is not surprising: generality is linked to continuity, and it is the presence of continuity in experience that enables us to say that we experience real generality. But we still face the problem of how the metaphor helps: we would expect the composite of a continuous series of modifications of images of buildings, for example, to be an undifferentiated mess.

Although the ideas are different, many readers may be struck by analogies between the claim that ideas are composite photographs and the Lockean claim that we form general ideas by abstraction. For Locke, we form our abstract idea of a criminal through performing an operation upon our different individual ideas of criminals: we eliminate

from these ideas everything that is idiosyncratic, everything that is not a feature of all. For Peirce too, we perform an operation upon our individual ideas or images: we superimpose them and expose the photographic plate so that those features which are common to all the individual ideas acquire prominence and those which are more idiosyncratic disappear from view. And the two views face a similar pair of problems. First, it most cases, it seems, nothing very distinctive or useful will result from this operation: there may be no characteristics that are common to all criminals, that remain when everything idiosyncratic has been eliminated. Or what does remain may be too limited to explain our understanding of the concept or idea. And second, if something does remain, it will be an idea or image of a particular face, albeit one that was constructed out of other particular faces that we have encountered and that was, perhaps, rather blank and lacking in character. The abstractness of the idea, and the compositeness of the photograph, do not seem to explain how our ideas can be general. The solution to this second problem calls for a more detailed account of how we can use this schematic idea or photograph in applying our general concepts. Perhaps the references to Kant’s schematism show how the Peircean claims avoids the difficulties that Locke’s account of abstract ideas faces.

5. Schematism

The schematism is one of the most puzzling parts of the Critique of Pure Reason, but it is one whose importance and promise was not lost of Peirce. He remarked that:

[Kant’s] doctrine on the schemata can only have been an afterthought, an addition to his system after it was substantially complete. For if the schemata had been considered early enough, they would have overgrown his whole work. (CP 1.35.)

The breakneck hurry in which the C.d.r.V. was written is its only defence against a charge of slovenly workmanship. Every detail is left in the rough; and there is no more unfinished apartment in the whole glorious edifice than that he devoted to the Schematization of the Categories. Kant says that no image, and consequently we may add, no collection of images, is adequate to represent what a schema represents. If that be the case, I should like to know how a schema is not as general as a concept. If I ask him, all he seems to answer is that it is the product of a different “faculty”. (CP 5.531)

The first passage attests to the power of these aspect of Kant’s thought, and the second suggests that, even if Kant did not fully work this out, the Schematism contains the matterials for an adequate understanding of general concepts. But both suggest that the details of Kant’s theory were not to Peirce’s taste. Circumstantial evidence suggests that the material about composite photographs is part of a way of thinking about ideas and concepts which develops some of the themes that surface in this section of Kant’s book and which is fundamental to Peirce’s pragmatism.

The concern of the schematism is with how concepts, the creatures of the understanding, are applied to the empirical world, applied to the objects of empirical intuition that appear to us in space and time. Imagination provides the link: each concept is allied to a schema whose role in the reproductive imagination provides a sort of rule for the anticipation of experience. The details are sufficiently obscure and difficult that they need not concern us here. From our discussion so far, it will be evident that Peirce’s appeal to composite photographs is intended to provide an account of general concepts which meets this need: the composite photograph is a schema whose representation in the imagination yields something that can be compared with and or applied to sensory experience. Moreover the appeal to photographs is intended to capture the pragmatist insight that these general ideas and schema need contain no conceptual elements which cannot have their source in experience. The pragmatist principle, we might conjecture, shows how general concepts can be schematised; and the composite photograph metaphor helps to make plausible the idea that all ideas can be schematised in this fashion.

Here is one passage which fills in some details. Considering Bain’s suggestion that generalization on the basis of experience of associations is the effect of “an effort of similarity”, Peirce says:

Why not say, at once, it is the first half of a suggestion by similarity? I am trying to recall the precise hue of a certain emerald that my mother used to wear. A sequence of shades runs through my mind. Perhaps they run into a continuum; but that makes no difference. They are a multitude of colours suggested by that one colour. Conceived under what Kant imperfectly described as a rule or schema, they constitute a general conception of a green something like that emerald …

The vague memory of a sensation is just an aggregate, whether continuous or not makes no difference, of ideas that are called up together by a suggesting idea. (CP 7.407)

The composite photograph metaphor seems to be concerned with how a multitude of experienced ideas can be fused into a single representation, the photograph. This passage seems to suggest the reverse process: the single representation, the idea, calls up, or generates a sequence of shades, a sequence of particular images or photographs. And the example captures two things that are important for the schematism: the idea generates particular representations in the imagination or in the form of images; and the logical structure of the idea is displayed in time in a sequence of images.

A theme in Peirce’s theory of perception will help us to see where this idea can lead. As we saw, perception involves an abductive inference, albeit an ‘acritical’ one. Suppose I see a chair. The judgment that it is a chair is not derived as a conscious inference from more primitive premises which describe the qualitative character of the percept. Rather the inference is immediate and ‘acritical’ and it infects the qualitative character of my experience itself: the object presents itself to me as a chair. Sometimes this is described as the ‘limiting case’ of an abductive inference. This claim is supported by appeal to cases where what is seen is under our control – we can control whether we see the picture as of a duck or a rabbit, as of a young girl or an old woman, as of stairs going up or down, or so on. The imagination is involved in this process, and it involves anticipating how the scene will develop. If the ‘rabbit’s ears’ suddenly open and spear a fish, our experience loses its coherence and we adopt the new perceptual abduction that we were looking at a duck. The form taken by these abductive perceptual judgements involves sensuous anticipation of how things will develop, and, we might suppose, imagination is needed to fuse the qualitative and the judgmental in this sort of way. The concepts we apply in perceptual experience and judgment anticipate continuous development in the quality of our experience, and such continuous development can be confirmed by (or confuted by) the experience we actually have. Peirce’s writings on pragmatism from 1903 emphasise this broad picture. I am suggesting here that he found echoes of these claims in Kant’s schematism and, also, that the ‘composite photograph’ metaphor helped Peirce to think about this dark and difficult themes. The idea that infuses perceptual experience provides a sort of iconic representation of how experience will develop, or of how experience will be if its objects are of the kinds we take them to be. Composite photographs provide one exemplar of something that might do this sort of job without bring to experience any contents we can think of as a priori. The composite owes its content entirely to the impact of light upon the lens, and it provides an exemplar against which things can be judged.

If there is any plausibility in this account of the appeal for Peirce of the composite photograph metaphor, it raises a number of questions of interpretation. First, Galton style composites are available for, at best, a very small number of concepts which are applied to experienced items on the basis of how they look. We need an understanding of the metaphor which has a much wider application. Just what would a composite photograph of a moral ideal be? Or of an electron? Or of a building? The Galton model must be stretched and developed if it is to have the general application that Peirce seeks. Second, Galton style composites are static: they are like snapshots of criminal types or learned scientists. As Peirce recognizes, Kant’s schematism makes essential reference to sequences of intuitions in time. And the examples we have just used to make plausible the connections between Peirce’s position and Kant’s have also appealed to the role of composites in recording the continuous spread and development of ideas. What we need is more like a composite film than a composite snapshot; and the prospects for informative composite films on the Galton model are very poor indeed.

6. Conclusion and conjecture

It is difficult to make much progress with this, but the following conjecture may show the way forward. It seems obvious that Peirce’s use of the composite photograph metaphor commits him to claiming that we can understand ideas as ‘made out of’, or ‘composed of’ large numbers of particular experiences or ‘photographs’. The question we must ask is: how does this composition work? Galton’s work suggests one story. The difficulties we have seen the view facing, and the analogies we have noticed between Peirce’s apparent claim and the Lockean theory of abstract ideas, have depended upon assuming that Peirce’s account of the ‘composition’ of ideas employs a story that is largely true to the Galtonian mechanism for constructing composite photographs out of individual ones. However several of the passages from Peirce that we have cited suggest a different story, a different account of how general ideas are compounded out of particular ‘photographs’.

Consider an example Peirce employed in a paper that dates from before his exposure to composite photography, ‘The doctrine of chances’.

When a naturalist wishes to study a species, he collects a considerable number of specimens more or less similar. In contemplating them, he observes certain ones which are more or less alike in some particular

respect. They all have, for instance, a certain S-shaped marking. He observes that they are not precisely alike, in this respect; the S has not precisely the same shape, but the differences are such as to lead him to believe that forms could be found intermediate between any two of those he possesses. He, now, finds other forms apparently quite dissimilar – say a marking in the form of a C – and the question is, whether he can find intermediate ones which will connect these with the others. This he often succeeds in doing in cases where it would at first be thought impossible … In this way, he builds from his study of Nature a new general conception of the character in question. (W3: 276-7)

Note some features of this case. The new idea results from the naturalist’s experiences of specimens: in this, it resembles a composite photograph. The idea generates a continuous series of actual or possible experiences. The possible experiences can then be used to test the idea against experience: actual experience can be compared with these anticipations of experience. Although it is not a single ‘photograph’ which contains all the others, it is still a composite of a continuous series of possible photographs, of possible experiences. The idea provides a rule that generates a continuous array of concrete ideas, and these can be used to recognize or make sense of the further experiences that we have. I recognize a specimen of this kind when the idea generates an iconic representation which fits the experience. This can occur habitually and acritically; and, presumably, it can also occur through conscious reflection and deliberation. So, although the mode of ‘composition’ is not the same as Galton’s, we can see marked analogies between general ideas so understood and composite photographs.

In that case, the idea generates a continuous spread of iconic representations which vary along the dimension described. It is easy to see how most ideas will embody continuous variation along a large number of ‘dimensions’. We can also see how the application of the concept may be quite a complex matter: some dimensions may matter more than others; vagueness and indeterminacy are likely to be involved; and so on. The important point here is that we can understand a different mode of ‘composition’ which can still fit the metaphor. There is one important difference. When we construct an idea is this manner, we do build it out of cases we have known, out of the actual photographs. But the idea will contain many elements that have not been experienced. We form ideas of possible specimens that fill the gaps along the different dimensions. But, as is suggested by Peirce’s pragmatism, the cases that we add do not differ in kind from those that we have experienced. All are experiencable and, as the cited passage suggests, we test our idea by looking for examples of

the sorts of cases we have added. The idea contains nothing that cannot be an object of experience.

Time has still not entered the picture, but it is easy to see how it does so. My idea of a duck will also trace ways in which the appearance of a duck can change. Its appearance will alter as I move round it, as it walks closer or further away, as it turn around, as it takes off and flies, and as it matures from duckling to full grown duck. Once again, we do not need a single snapshot that records this information. But it provides further possibilities of continuous growth and change which can be recorded in the continuous series of iconic representations that the idea can generate in the imagination. So the general picture: the content of an idea is exhausted by a listing of the complex system of iconic representations, varying along a number of continuous dimensions including time, and which can serve as templates for perceptual abductions. Moreover many of these iconic representations have been obtained through perception; and the others all represent states of affairs that can, in principle, be experienced.

This leaves more abstract ideas such as moral ideals, theoretical entities such as electrons, mathematical ideas, psychological states and the like. The question how to apply the composite photograph metaphor to these is, in large part, the question of how we can clarify such concepts using the pragmatist principle. And that is too large a problem to take on here. However the present conjecture does answer one difficulty we might have in applying the metaphor to such cases. Galton’s composite photographs are all of things that have a distinctive look, and moral ideals, numbers, electrons, and states such as anger don’t have such ‘looks’. If ideas can be composite through being systems of iconic representations which vary, in many cases, along many continuous dimensions, then it is easy to see how there can be such ideas of things which do not have any distinctive look. My idea of anger may generate icons of how people behave when angry, of how they justify their anger, of how their anger can abate, without offering a single schematic picture of anger as such. [12]

Notes

[1] For references to Peirce, I use standard forms of reference. Wn.mm refers to Writings of Charles S. Peirce, Bloomington: Indiana University Press, by volume and page. CPn.mmm refers to Collected Papers of Charles S. Peirce, edited by Charles Hartshorne and Paul Weiss, Cambridge: Harvard University Press, by volume and numbered sections. And Epn: mm refers to The Essential Peirce, Bloomington: Indiana University Press, by volume and page.

[2] One exception to this is provided by a helpful note by Nathan Houser in EP 2: 504 n.10.

[3] Richard Robin, ‘Classical Pragmatism and Pragmatisms’s Proof’, in The Rule of Reason, edited by Jacqueline Brunning and Paul Forster, Toronto: University of Toronto Press, 139-152, at page 139.

[4] Much of Jastrow’s article is devoted to describing different techniques for obtaining the same effects as ordinary composite photographs, and indicating some of their more interesting features. Jastrow’s article, ‘Composite Portaiture’ is in Science volume VI, 165-7

An issue of the same journal in the following year, written by John Stoddart, was illustrated by composite portraits of undergraduates from Smith College: two versions of a photograph of some forty nine members of the previous senior class, and a photograph of twenty members of the class who formed an elective division in physics. His article pointed out some of the decisions one must make in creating composite photographs. Science volume VIII, 89-91.

[5] See Nathan Houser’s introduction to W4: xxxv.

[6] At the time of writing, these pictures are available on Burson’s web site at http://www.nancyburson.com/ec/ec1.html. Another of Nancy Burson’s examples is equally fascinating, her 1983 piece ‘Big Brother: Stalin, Mussolini, Mao, Hitler, Khomeini’, produced for a CBS programme on 1984.

[7] About Faces, New York: Doubleday, 1989.

[8] Francis Galton, Inquiries into Human Faculty, London: Dent, 1907 (2nd edition), page 11.

[9] See Karl Pearson Life, Letters and Labours of Francis Galton, Cambridge University Press, 1914-1930. p.286. There are also some illustrations of composite photographs of different kinds of criminals at this reference.

[10] CP 2.441 tries to extend the idea to apply to universally quantified propositions. I shall not consider that here.

[11] Hookway Peirce, London: Routledge, 1985, chapter six and Truth, Rationality and Pragmatism, Oxford: Clarendon Press, 2000, chapter three.

[12] Many thanks to Nathan Houser for a very helpful discussion of this topic and for providing access to material in the Peirce Edition Project’s files, especially the articles in Science. Jennifer Saul helped too by telling me about the Nancy Burson composites and by commenting on an earlier version of the paper.