A Motive (n.) is wrongly pictured as a cause seen from the inside — a cause we are immediately aware of — because one word, 'why', asks for both.
A Motive (n.) is judged by the author's word, witnesses, prior history — and it is a peculiar language-game, since tables and stones have none.
A Motive (n.) is asked of me not because I know events in my mind, but because evidence and consequences of my statement are of another sort.
A Motive (n.) differs from a cause in how it is found out; stating a motive may resemble stating a cause, except for the one confessing it.
A Motive (n.) in the saying he alone knows his motives expresses the fact that we ask him, and if he is sincere he will tell us, but sincerity is not enough for guessing them.