Knowledge-Of and -That

To finish off this mini-series about kinds of knowledge, I want to consider the relationship between knowledge-of and knowledge-that. We have already said that both rely on knowledge-how. One might therefore think that one could have either one without the other. I have not given any reason to think otherwise.

Instead, I want to argue that they are equally basic but not independent. I do not claim that to possess knowledge-of one must also require knowledge-that or vice-versa, but that, if one can possess knowledge-of, then one can also possess knowledge-that, and vice-versa.

Knowledge-that requires the ability to use language to communicate to others what one knows and the ability to operate on propositions logically. This linguistic requirement entails the requirement that one be able to know others personally. To be able to communicate a proposition in a language, and thus, on my account, to know a proposition, one must know how to use language. The use of language, in turn, requires the ability to recognize others as possessing mentality, for instance, recognizing others as meaning something, as aiming at some goal, etc.

If one has this ability, then one is able to achieve knowledge-of people. Knowledge-of is built out of an understanding of the mental architecture, as it were, of another: the other's abiding mental features, such as their hopes and fears, the way they feel and think, etc. This underlying ability is, moreover, sufficient, together with a general capacity for knowledge in general (that is, the ability to retain this recognition), for knowledge-of, and likewise for language and knowledge-that.

This claim, that the ability to recognize others as possessing mentality is sufficient for learning language, may seem like an odd claim. It seems contentious whether animals possess such a capacity. I therefore owe an argument for that claim.

Particularly with respect to propositional knowledge, language's distinctive feature is its ability to refer to things and attribute predicates of those things. My claim is that our ability to recognize and know others' mental features, together with the ability to retain such knowledge, enables us to recognize objects as subject to referential relations, in part because it enables imaginative activity. We are able to retain another's attitudes toward things and thus are able to retain a kind of link between sounds and objects which is flexible enough for language. Attitudes which embed further attitudes depend on a reciprocity of this kind of knowledge of other minds--A fears that B hopes that C intends to come tomorrow--and permits this embedding in language and thereby permits full-fledged language.

This is just a sketch of my account, and others may run things differently, perhaps arguing that language enables what I have counted as the more basic capacities. The problem with running it backwards is that it makes it harder to account for the origin of language if one needs language in order to recognize others as minded. If we instead suppose that humans come into the world with certain capacities to recognize others, and that language builds on this, then we can account for the origin of language without magic.