Full Idea
The subject is not a substance but a form, which is not always identical to itself. You do not have the same relation to yourself when you go to vote and when you seek to fulfil your desires in a sexual relationship.
Gist of Idea
A subject is a form which can change, in (say) political or sexual situations
Source
Michel Foucault (Ethics of the Concern for Self as Freedom [1984], p.290)
Book Reference
Foucault,Michel: 'Essential Works 1954-1984 I: Ethics', ed/tr. Rabinow,Paul [Penguin 1994], p.290
A Reaction
I don't think I believe this. If it were true, the concept of 'sexual politics' would mean nothing to me. A brutal or sympathetic nature is likely to express itself in both situations.