Strawson’s ‘basic argument’ for the non-existence of personal freedom is as follows: What you do is determined by how you are. So you are responsible for what you do only if you are responsible for how you are. But you are not responsible for how you are, since how you are precedes any possible action of yours and in any case is a function of the condition of the universe before you even existed. So you are not in any way free and are therefore not morally responsible for anything.
I do not believe that this argument goes through. For a behavior on x’s part to be ‘free’ is for that behavior to arise in a certain way out of x’s psychological structure. If x has an epileptic fit, his bodily spasms do not arise in the appropriate way out of x’s psychological structure and therefore are not free. If x robs a convenience store, x’s conduct does so arise and is therefore free. It may well be that x’s behavior is predetermined by forces outside x’s control, but because those forces operated through x’s own agency, x is responsible for them.