While reading Atkin’s Chapter 4 on Peircean semiotics, I learned that the 3 aspects of a sign (sign-vehicle, object, and interpretant) are not different entities. Rather, they are interdependent and are parts of a single whole. It is difficult to see the interpretant as a “thing”, something that is easier in the case of sign-vehicle and object, as the interpretant seems more like a process, something that happens (the “immediate object” is similarly closer to a passing impression than a stable entity).

“The importance of the interpretant for Peirce is that signification is not a simple dyadic relationship between sign and object, as it is for someone like Saussure. Rather, a sign signifies an object only in the course of being interpreted.” (Atkin, 2016, p. 128).

Similar to how a sign is determined by its object, a sign “determines an interpretant by using certain features of the way the sign signifies its object to generate and shape our understanding. So the way that smokes generates or determines an interpretant sign of its object, fire, is by focusing our attention upon the physical connection between smoke and fire.” (Atkin, 2016, p. 131)

What is still puzzling to me, is (something I wrote about in the previous post) this: “… every interpretant is itself a further sign of the signified object.” (p. 135)

Icon, Index, & Symbol

I should also note that my simplistic understanding of icon, index, and symbol, which I had since the early days of graduate school didn’t hold up. I used to think about the three as different kinds of things and clearly distinguishable. A picture of a bird was an icon, a bird nest was an index, and an opaque line-drawing could be a symbol of birds. It would be more apt to see them as corresponding to three different functions, functions that could be served–to varying degrees–with one and the same sign. I think we can see icons, indices, and symbols as different modes of presentation (Frege) for objects.

  • An icon emphasizes a particular qualities of an object. I could use a peacock feather as a symbol of the bird, but by virtue of emphasizing featheredness of the bird, however, the feather also functions as an icon. Thus, the mode of presentation related to icons brings objects qualities into focus.
  • An index, by contrast, emphasizes an existential fact about an object (its presence, its history, etc.). The feather could be a gift from a childhood friend. By showing the feather, I could be telling my friend that, despite all the years passed, I still have his gift. Thus, the mode of presentation related to indices brings into focus the objects’ existence, identity, history, and so forth. The concept of gift is, of course, mixed as it relates to conventions and symbols, which leads us to the third category.
  • A symbol emphasizes a particular convention related to, or signified by, the object. The feather could stand in for birds in general or for peacocks according to the local conventions of a game. It could also signify membership in a particular community.

The relation between Jens Mammen’s (2016, 2017) logical foundation and Peircean semiosis is now clearer to me. To recall, Mammen divides our capacity to categorize into two sub-domains: (1) the capacity to categorize objects with respect to a general feature and (2) the capacity to categorize individual objects regardless of their features. Indices are most clearly connected to choice categories. Both choice categories (Mammen) and indices (Peirce) prevent infinite semiosis and the trap of idealism (i.e., no contact with real objects). Both frameworks require:

“… singular propositions and individual variables for objects that cannot be picked out by definite descriptions. Peirce treated these non-general signs as indices, which in turn led him to identify the index as an essential part of logic.” (Atkin, 2016, p. 141)

“… Peirce sees the indexical signs as serving a very particular indicative purpose, that if creating connection with its object.” (Atkin, 2016, p. 149)

Thus, choice categories seem to result from, and require, indexical signs. It would be an intriguing task to try to connect the function of symbols (and the corresponding domain of conventions) to choice categories. In one respect, when we are within a convention (taking it for granted) symbols would appear to have general features (i.e., Mammen’s sense categories). In another respect, just prior to entering into a convention, adopting its rules and symbols, we can recognize the particularity and arbitrariness of symbols (the view from outside a given convention).

I am not going to discuss the important concepts of immediate object (~profile) and dynamic object (~object in itself), or the interesting connection between these two and phenomenological themes (varieties of presence). For now, let me just note that the recognition of the difference between immediate objects and dynamic objects corresponds, respectively, to the recognition between sense categories and choice categories (Mammen, 2017).


Atkin, A. (2016). Peirce. Routledge.

Mammen, J. (2016). Using a topological model in psychology: developing sense and choice categories. Integrative Psychological and Behavioral Science50(2), 196-233.

Mammen, J. (2017). A new logical foundation for psychology. Springer.