Philosophy, Psychiatry, & Psychology

Philosophy, Psychiatry, & Psychology 9.1 (2002) 35-39

The Ownership of Thoughts

John Campbell

Keywords: schizophrenia, thought insertion, immunity to error through misidentification.

SYDNEY SHOEMAKER FORMULATED a basic point about first-person, present-tense ascriptions of psychological states when he declared that they are, in general, immune to error through misidentification (Shoemaker 1984). Assuming Shoemaker's point to be correct, the puzzle it raises is this: how are we to explain this datum? Why should it be that first-person, present-tense ascriptions of psychological states are immune to error through misidentification? One type of explanation is in terms of the meaning of the first person: that "I" just stands for whoever is the owner of these (demonstrated) psychological states (including any states being self-ascribed). I argued against this account of the first person in a number of places, and in favor of an alternative explanation of Shoemaker's datum. On the alternative explanation, the reason for the immunity is provided by an account of the ownership of psychological states, on which what makes a psychological state mine is the possibility of self-ascription of it by me (Campbell 1986, 1999a). Suppose we call this the Introspectionist explanation of the immunity to error through misidentification of present-tense self-ascriptions of psychological states. I do think, though, that the simple Introspectionist account is too simple an account of Shoemaker's datum (Campbell 1999a, 1999b). The reason is that there is a certain complexity in our notion of the ownership of a token thought. We cannot give a full account of our ordinary notion of the ownership of a thought simply in terms of the person who is capable of introspective knowledge of the thought. The reason is that there is another dimension to our ordinary notion of the ownership of a thought. We also think of the possessor of a thought as being the person who generated that very thought; we think of the owner of the thought as being the person who brought that particular token thought into existence, the person who formed it. Of course, that token thought may be a copying of someone else's idea; that other person may have influenced my formation of that particular thought. But the point remains that I play a special role in the production of my thoughts.

Suppose we have a document bearing a signature and we ask, "Whose signature is that?" In this case we are asking about the authorship of the signature; we are asking who made those particular marks on that bit of paper. Of course, someone else can copy my signature, trying to make it look as if what they write was written by me. But for a particular piece of writing to be an authentic signature of mine, the thing has to be generated by me personally. I think it is helpful to bear in mind this aspect of the notion of the ownership of a signature, when we consider a certain complexity in the notion of the ownership of a thought—I mean, an occurrent, episodic [End Page 35] thought. There are, I am saying, two strands in the ordinary notion of the ownership of a thought, which we do not ordinarily have any reason to separate. First, there is the notion of the person who generated that particular thought, which we might think of on the model of the person who inscribed a particular signature. Of course, in generating a particular token thought, you may be subject to all sorts of influences. Perhaps your thought is derivative, largely shaped by others. Perhaps your thoughts are sometimes simply echoes of the things other people have said. Nonetheless, when we consider how your individual token thoughts are being brought about, you play a proximal role in their formation that no one else does. To give an analogy, suppose that I am taking notes at your dictation. Then there is a sense in which the contents of my notes are entirely determined by you. But there is also a sense in which the token sentences are being generated by...