Readings
Texts
- Hilary Putnam, "The Meaning of 'Meaning'"
- Andy Clark & David Chalmers, "The Extended Mind"
- Hilary Putnam, "Introduction to 'The Twin Earth Chronicles'" (from last time)
- Jerry Fodor, "Where is My Mind?" (LRB)
Synopsis
We began today by asking, what would an argument for 'tagging' or direct reference, as opposed to mediate reference, look like?
To rehearse, at the crudest level of explanation intentionality is the relation of States of Affairs (SofA's) X to Y whereby X is about Y. Thus a SofA consisting on the screen of an arrangement of pixels or on the page of an arrangement of ink which we call a sentence,
The cat is on the mat.
is about
The cat's being on the mat.
whether the cat happens to be on the mat or not. That is, the sentence is about the the state of affairs it describes. Roughly, it is true if the state of affairs it describes obtains and false otherwise.
Yet the sentence, understood as a mere inscription, has at most derived intentionality. It is about nothing, it describes nothing, absent some English-user's interpretation. Thus the sentence 'means' what it means provided it can be taken to have that meaning. The sentence's (derived) intentionality presupposes the English-user's (original) intentionality. Put another way, the sentence has the meaning it has only to the extent that it is understood to have that meaning. Yet understanding is presumably a psychological state. Apparently, then, original intentionality is a special relation between psychological states and the states of affairs they are about. This is the insight behind Brentano's Thesis.
Surely, then, the nature of my psychological states should determine what they are about. My thoughts are about the world, but they are first and foremost my thoughts.
A problem with this view emerges when we consider linguistic communication.
Let us suppose, as seems natural, that knowing the meaning of a term is to be in some particular psychological state with respect to the term.
Let us further suppose that the meaning of a term determines its reference, as again seems natural.
Then under the physicalist assumption that there cannot be a difference in psychological state without a difference in physical state, we conclude that, in using a term, there cannot be a difference in reference without a difference in physical state.
Following Putnam, though, we find that "water" as I use it on Earth differs in reference from "water" as my Twin-Earth counterpart uses it, even though I and my Twin-Earth counterpart are micro-physical duplicates. Hence there can be a difference in reference without a difference in physical state. What my psychological states are about seems to have nothing to do with my psychological states per se. Meanings, as Putnam memorably puts it, "ain't in the head!"
This is an admittedly condensed way of putting the problem. Suffice it to say that the problem of intentionality inherits results from the philosophy of language (a fact which should be obvious when we reflect on what we mean by "intentionality"), and those results are not always happy for the philosophy of mind.
Putnam's Twin Earth Thought Experiment leads to his denial that meanings are part of the furniture of a private theater of the mind. Thus we have the problem of understanding where, precisely, the mind stops, because if Putnam is correct in claiming that "meaning's ain't in the head!", then the mind does not stop at the skin as we normally understand it does. Call this externalism, the idea that cognitive functions are not merely the result of neurological processes but include also wider communities and, perhaps, features of the environment.
Pursuing externalism further today, we began by wondering where the mind starts and stops. A convenient place to draw the boundary of the mind is at the skin: Our minds go no further than our bodies. An intriguing hypothesis is that the mind does not so sharply coincide with the body. Rather, cognitive processes extend beyond the body to encompass, for example, communication and information technologies.
Unfortunately, our investigation of intentionality must stop at this bewildering possibility. It turns out there are a number of further challenges to the possibility of understanding the mind vis-a-vis Dretske's Dictum, and we must make room for them.
Next time, once we've returned from Spring Break, we turn to the hard problem of consciousness, which has been justly called the most difficult problem facing science today.