Albert Einstein tycks, som jag, inspirerad av Arthur Schopenhauers syn på den fria viljan. Så här skriver Einstein i Ideas and Opinions:

I do not at all believe in human freedom in the philosophical sense. Everybody acts not only under external compulsion but also in accordance with inner necessity. Schopenhauer’s saying ”A man can do what he wants, but not want what he wants,” has been a very real inspiration to me since my youth; it has been a continual consolation in the face of life’s hardships, my own and others’, and an unfailing well-spring of tolerance. 

Schopenhauer-citatet sätter fingret på det centrala. Visst kan vi höja fingret om vi vill, men valde vi att vilja det? Med andra ord: Är vi orsaken till vår egen vilja, causa sui? Om inte, har vi inte fri vilja.