Full Idea
What is left over if I subtract the fact that my arm goes up from the fact that I raise my arm?
Gist of Idea
What is left over if I subtract my arm going up from my raising my arm?
Source
Ludwig Wittgenstein (Philosophical Investigations [1952], §621)
Book Reference
Wittgenstein,Ludwig: 'Philosophical Investigations', ed/tr. Anscombe,E. [Blackwell 1972], p.161
A Reaction
Wittgenstein's implication seems to be that nothing is left over, but I would have thought that the will was the thing left over when you decide to raise your arm, but then discover that you are paralysed.