Thursday 2/27

Robot Intentionality IV: Dennett's Response






Dretske, we recall from last time, thinks original intentionality is woven into the fabric of the universe in virtue of the causal relation. The lowly compass, indicating as it does the magnetic north in virtue of its causal relationship and thereby being about the magnetic north (in an admittedly attenuated sense) exhibits original intentionality. To be sure, this is not the full-blown, tough-nut-to-crack intentionality our cognitive functions enjoy, yet it is enough, Dretske thinks, to respond to Searle's skeptical challenge.

The particulars of Dretske's argument that the compass exhibits original intentionality can be found in the handout on Dretske's Argument. Suffice it to say that Dretske has an intriguing argument which bears further scrutiny.

If Dretske's Argument is successful, then the problem of intentionality dissolves. That is, if the lowly $1.99 compass exhibits original intentionality, then our problem in building minds is not that of building something that exhibits original intentionality. We can already do that, and quite well. Instead, our problem is that the original intentionality exhibited by the compass is substantially less 'feature-rich', if you will, than it would need to be to be useful in building minds. Let me explain.

The original intentionality exhibited by the compass is a function of its causal relation to the Earth's magnetic field. Yet this causal relation is constant: In the absence of stronger magnetic fields, the compass will always and consistently point to the magnetic north. Indeed, in the 'presence' of stronger magnetic fields, it will point to their 'magnetic north', if you will. Thus the compass is veridical. It always points to the magnetic north, which is of course why the compass is such a useful instrument for navigation.

Beliefs and other intentional states of mind are not, however, veridical. Unlike compasses, beliefs can be mistaken. The cow in the field might cause me to form the belief that there is a horse in the field late in the evening. Worse, why does the state-of-affairs of the cow's being in the field cause me to believe that there is a cow in the field, if it does, but it doesn't cause me to believe that there is either a cow or a horse in the field? In short, a belief can misrepresent a state-of-affairs, and is not at all clear if a belief represents a state-of-affairs that it represents that state-of-affairs at all. To further complicate matters, consider that desires are never directed on existing states-of-affairs. Rather, the desire that there be a horse in the field represents the non-existent state-of-affairs of a horse being in the field, but it does not thereby misrepresent even though it is strictly speaking false that there is a horse in the field. Mental representations can be in error, but being in error is not always the same thing as misrepresenting.

Intentionality as it applies to mental states goes far beyond the simple causal, veridical relation that secures, Dretske argues, the compass' original intentionality. Dretske thinks he can secure a richer intentional basis to allow for misrepresentation by introducing the notion of a natural function--an indicator, that is, which indicates the presence of an F, quite apart from our reading it as indicating the presence of an F, and even if it is caused to indicate the presence of an F by the presence of a G.

We'll begin with that argument next time.