The interest contemporary philosophy takes in Kant's notion of apperception is restricted to his criticism of the Cartesian Ego and to his refutation of scepticism, but there is a profound lack of concern for the notion itself and for the act of spontaneity in particular which is connected with the use of the word T. Starting from a comparison of Wittgenstein's account of this use with Kant's considerations it is argued that the latter aims at a theory of formal conditions (...) of knowledge which includes the availability of the notion of the I. It is clarified what the determination of apperception as an 'act of spontaniety' amounts to (B: 132). Kant's scattered remarks on the ability of having the representation of the I, of using the word 'I', are considered in order to show that what he called 'the logical I' has something to do with the capacity of performing an act of judgment. It is argued that such an account is not to be found in contemporary discussions of 'essential indexicals', 'first-person view' and mental self-ascriptions. (shrink)