Noticing Aspects

by Carl Pierer


Fig. 1

Part II of Wittgenstein's Philosophical Investigations, also known as Philosophy of Psychology – A Fragment, contains a lengthy treatment of perception. He begins by drawing a distinction:

Two uses of the word “see”.

The one: “What do you see there?” – “I see this” (and then a description, a drawing, a copy). The other: “I see a likeness between these two faces” – let the man I tell this to be seeing the faces as clearly as I do myself.

The importance is the categorical difference between the two ‘objects' of sight. (PI, p. 193)

The first ‘object' of perception is a something, an entity that is being perceived. It can be reproduced by drawing a picture of it. The second ‘object' is more puzzling. Where is it to be located? What does it mean to see the likeness? It cannot be located within the object of perception (what is seen in the first sense), for it is a different way of seeing. Indeed, it is not something that can be externalised. I cannot show the likeness I see to the interlocutor. Wittgenstein continues:

I contemplate a face, and then suddenly notice its likeness to another. I see that it has not changed; and yet I see it differently. I call this experience “noticing an aspect”. (Ibid.)

This process, where one perception falls into an entirely different one, is not simply a distortion happening in rare scenarios but ubiquitous. For example, when the airplane takes off and I am looking out the window, I can see how the cars and houses get smaller and smaller. At first, they have their normal significance, they look just like cars, like houses. But suddenly, a change happens, and this picture falls into a different one, where cars and houses look unreal. They now look more like toys than the life-sized objects they are. My perspective has changed somehow and I can no longer see the house as one I could enter.

Wittgenstein's own example is that of the “duck-rabbit” (Fig. 1), the familiar picture from Gestalt psychology. We notice distinctly how we move from seeing a duck to seeing a rabbit. This is only part of its paradoxical air, for at the same time we are under no illusion that the picture itself has changed. What changes, when we see the shift from duck to rabbit, is nothing in the picture.The visual input we receive from the picture remains constant, yet the figure is altogether different. We might even exclaim ‘now it's a rabbit', which only furthers the paradox. For we employ such sentences to denote a true, observable perceptual change (for instance, when the picture of a duck is replaced by a picture of a rabbit in a film). Nonetheless, we are also inclined to utter it in this context, where the visual input remains constant. What, if anything, is it then that changes? And why does the change occur?

Initially, there seem to be two possible answers. One possibility would be to hold that a visual experience is reducible to a physiological process. We will have to then go on to search for a physiological explanation of the phenomenon. But any such explanation could not possibly be satisfying. The problem here is that we have a use for the concept of “noticing an aspect” or “aspect-dawning”, which is independent of any physiological description of an underlying phenomenon. As Mulhall puts it: “If those phenomena are not the grounds upon which the concept is applied, their introduction as a revelation of the ‘real' meaning of aspect-dawning in fact constitutes a redefinition of that concept rather than an elucidation of it as it stands; so they cannot account for the paradox which is central to the present structure of that concept.” (Mulhall, p. 7) The idea here is really rather subtle: the meaning of aspect-dawning is grounded in the way we employ the term. But, because nothing physiological figures in our use of the concept (we do not think of what is going on physiologically when we employ it), telling a story about the physiological processes would not be able to explain the paradoxical nature of the concept itself. In other words, the physiological narrative could not transition from the meaningless visual inputs to the conceptual paradox.

Facing the impossibility of a physiological explanation, we are pushed towards thinking of the problem as an inner change. Perhaps, indeed, it is an inner representation, something about the way we organise the visual input which allows the transition from duck to rabbit. As Wittgenstein has the interlocutor put it:

I suddenly see the solution of a puzzle-picture. Before, there were branches there; now there is a human shape. My visual Impression has changed and now I recognize that it has not only shape and colour but also a quite particular ‘organization'. (PI, p. 196)

On this view, we might be thinking of perception as consisting of having internal copies of the external world. When we see a box, somewhere in us resides the picture of a box. There is a certain way we ‘organise' visual inputs to form a representation, and seeing, perceiving, just means to have this representation. One key feature here is that such a representation would be deeply personal: although we can think of it as a picture or entity present to us that can be described just like anything else, only the perceiver has access to it. It would be a private object.


Fig. 2

But again, suspicions about private objects aside, such a view could not account for what is going on. Wittgenstein continues the above-quoted paragraph: “My visual impression has changed; – what was it like before and what is it like now? – If I represent it by means of an exact copy – and isn't that a good representation of it?- no change is shewn.” (Ibid.) If first, when looking at the duck-rabbit, we have an internal representation (an exact copy) of the duck in the picture and then, when we see the rabbit, we have an exact copy of the rabbit, we do not have a change at all. They are two distinct pictures and just like above, this view could not distinguish between the change of aspect-dawning and changing the picture entirely (as for example in a slide-show).

Does the vain of this argument not run very much like Merleau-Ponty's argument against the constancy-hypothesis? Merleau-Ponty sets out to show the insufficiency of a view that rests on postulating a direct correspondence between the visual givens and what we see, by illustrating its incapability to explain the tension present in optical illusions. Looking at Fig. 2 the lines appear skewed. Yet, the subtlety lies in the fact that we are not quite sure. From one instance to the other, it seems as if our perception falls from “they are skewed” to “they are parallel”, and back again. There is an unresolved ambiguity. It is precisely this ambiguity that lets us determine that it is indeed an optical illusion and not simply a picture of skewed lines. Now, a theory that merely takes perception to be nothing further and above the visual input we receive cannot possibly make sense of this for the visual input remains constant, unchanged, whilst we have the ambiguous perception.

The second point Wittgenstein works out against this view is the following: as the noticed change seems to go beyond what is internally represented (the colours, shapes, ‘organisation, etc.), expressions such as “now it's a rabbit” cannot denote a proper change of the visual impression on this view. Instead, it is taken to be an indirect description. This means that such exclamations that denote ‘noticing an aspect' would be circumscribing a clear and distinct visual experience we have: when we say we see the picture as a box (Fig. 3), we really see a few lines on a page and then form an interpretation of these – giving rise to seeing it as a box. Yet, this would only make sense, Wittgenstein claims, if there was a direct way of describing the experience. When we say “the colour of the sky”, this only makes sense as an indirect description because we have the direct “the colour blue” ready at hand.


Fig. 3

Here, however, no more direct way is open to us. What is happening in aspect-dawning is that the noticing of the aspect, and hence reference to a representation, is not something additional to the experience. It is the experience. There is no more direct experience that we could possibly point to. “Aspect-dawning is characterized by the observer's felt need to employ a representation which might otherwise refer to subjective visual experience – to one way of seeing the figure – as if it were the report of a new perception.” (Muhall, p. 11)

This argument should be contrasted with Merleau-Ponty's invocation of the landscape that has been turned upside down. If we take picture of a landscape and flip it around, Merleau-Ponty argues, then its significance changes. It loses its appearance as a landscape and instead turns into something unfamiliar. For Merleau-Ponty, the intellectualist, for whom our perception is defined by certain structures and categories of understanding that we (inescapably) impose on the visual inputs, cannot make sense of this change – as the organisation of the picture remains the same. The trees, the mountains and the lake still are on the picture, they are still organised in the exactly the same way. Only the orientation of the photograph has been reversed, but this does not figure in the intellectualist's description of perception. In fact, the intellectualist's account falls short of capturing perception here in a way closely resembling to Wittgenstein's interlocutor trying to explain aspect-dawning via internal representations.

To summarise, Wittgenstein drew our attention to a distinction between seeing and seeing-as. He invoked the case of the duck-rabbit and similar examples to show that neither a physiological account of perception nor one invoking inner representations could possibly account for the phenomenon of aspect-dawning. It was hinted at possible similarities between the arguments Wittgenstein and Merleau-Ponty present in their attempts to grapple with optical illusions and the findings of Gestalt psychology in general. An in-depth comparison between them might properly address differences and show a closeness that is hidden by the presumption that they belong to opposed “schools”.



Merleau-Ponty, M. (2014). Phenomenology of Perception. (D. A. Landes, Trans.) London: Routledge.

Mulhall, S. (1990). On Being In The World – Wittgenstein and Heidegger on Seeing Aspects. London: Routledge.

Wittgenstein, L. (1953). Philosophical Investigations. (G. Anscombe, Trans.) Oxford.