Intentionality

Parallel to the question of how intentionality is possible at all is the question: How is it possible that intentional states have the particular content that they do? What makes my belief that in 2004 George W. Bush was president about George W. Bush, for example, and not about his brother, Jeb, or his father, George H. W. Bush, also named "George Bush," or about anything else?

There are two common answers to this in contemporary philosophy: a traditional answer called internalism, according to which the contents of the head are sufficient to fix intentional content; and a relatively recent answer (from the 1970s) called externalism, according to which the contents of the head are not sufficient. Some outside causal (Putnam, 1975) or social (Burge, 1979) relations not represented in the heads of intentional agents are also essential. The argument for externalism is always that two agents might have the same thing in their head and yet have different intentional contents. For example two agents might have the same thing in their heads associated with the word water, but if one agent had a causal history originating with H ₂O and the other had a history originating in some different but perceptually similar chemical, they would have different contents associated with the word even though the brains states were identical.

The reply given to this by the internalists is that in such cases the intentional content is determined indexically by indicating relations to the head or heads in question. By water, each person means the type of substance that he is familiar with or that his community has baptized as water. The situation is exactly like identical twins, each of whom thinks, "I am hungry." The contents in their heads may be of exactly the same type, but they determine different intentional contents, because the same indexical expression "I" refers to different people. It refers to whoever utters or thinks it. On this view there is nothing external about indexical intentional content. Type identical intentional contents may have different conditions of satisfaction because of internal indexical content. The dispute between externalism and internalism is very much alive.