Philosophy, Psychiatry, & Psychology

In thought insertion the subject acknowledges that a thought, CS3 (to use Chadwick's notation), occurs in his mind, but nevertheless maintains that CS3 is alien, which is to say, it is not his thought but rather someone else's thought. Why does CS3 seem alien to the subject?

We and Chadwick adopt a two-stage strategy for answering this question. In the first stage, both accounts attempt to explain why the subject picks out certain thoughts as candidates for alienation (i.e., ascription to another). In our view, the subject picks out CS3 because he has the sense that he is not the agent of CS3. He has the sense that CS3 is not something he thinks, where thinking is construed as action. In Chadwick's view, the subject picks out CS3 because he has the sense that CS3 is not contentually connected with (synthetically united to) his previous thoughts.

As both we and Chadwick recognize, these first-stage accounts do not explain why the subject regards CS3 as alien. As for ourselves, we readily admit that subjects often regard thoughts that don't occur by their own agency (e.g., thoughts that "just pop into one's head") as their own thoughts. Chadwick, for her part, readily admits that a subject may regard a thought as his thought even though it lacks contentual connections with his previous thoughts. So each sort of account needs a second stage in which the author explains why some, but not all, of the thoughts picked out in the first stage come to be regarded as alien.

In the second stage of our account we speculate that the subject regards CS3 as alien because it seems to him both (1) that the occurrence of CS3 requires an agentic explanation, and (2) that he himself is not the agent of CS3. Together, judgments 1 and 2 serve as the basis for the subject's inference that someone else is the agent of CS3.

For Chadwick, why does the subject regard CS3, but not other contentually disconnected thoughts, as alien? Chadwick mentions possible explanations but ultimately urges that the matter be settled by further investigation.

One candidate explanation is compatible with our account in terms of agentic considerations. It is quite possible that agentic considerations distinguish contentually disconnected thoughts and cognitive states that seem alien to the subject from those similarly disconnected thoughts that do not seem alien. Disconnected thoughts may be alien only when they are represented by the subject as another's actions.

Of course Chadwick may wish to develop her account in a manner that is incompatible with an agentic account. We say that a mental episode will seem alien to the subject only if it is an episode of the sort that the subject counts as a mental action. Our story purports to explain [End Page 115] how the subject could believe that another person's thinking is going on in the subject's mind. Our account thus leaves no conceptual space for alienation from mental nonactions such as physical sensations of pain or taste. Mental nonactions don't have agents, only subjects. Our account thus precludes the occurrence of delusions of pain insertion or taste insertion.

We are not aware of reports of delusions of pain insertion or taste insertion in the literature. However, note that if alienation from such "sensational" episodes does occur, that may be a good place for Chadwick to raise her hand and announce that her contentual account may hold conceptual room for such episodes whereas ours does not. Much depends on whether the notion of contentual connection and/or disconnection applies to sensational episodes. If the sorts of episodes that seem alien to the subject are always episodes that he regards as mental actions, then that would be something our account could explain. In the end, we certainly agree with Chadwick when she notes that more work is needed to settle the respective merits of, and the relations between, agentic and cognitive accounts. [End Page 116]