In the 500th edition of the programme, Melvyn Bragg and his guests discuss the philosophical idea of free will.Free will - the extent to which we are free to choose our own actions - is one of the most absorbing philosophical problems, debated by almost every great thinker of the last two thousand years. In a universe apparently governed by physical laws, is it possible for individuals to be responsible for their own actions? Or are our lives simply proceeding along preordained paths? Determinism - the doctrine that every event is the inevitable consequence of what goes before - seems to suggest so.Many intellectuals have concluded that free will is logically impossible. The philosopher Baruch Spinoza regarded it as a delusion. Albert Einstein wrote: "Human beings, in their thinking, feeling and acting are not free agents but are as causally bound as the stars in their motion." But in the Enlightenment, philosophers including David Hume found ways in which free will and determinism could be reconciled. Recent scientific developments mean that this debate remains as lively today as it was in the ancient world.With:Simon BlackburnBertrand Russell Professor of Philosophy at the University of CambridgeHelen BeebeeProfessor of Philosophy at the University of BirminghamGalen StrawsonProfessor of Philosophy at the University of ReadingProducer: Thomas Morris