How could we possibly appreciate the Mona Lisa if Leonardo had written at the bottom of the canvas: 'The lady is smiling because she is hiding a secret from her lover.' This would shackle the viewer to reality, and I don't want this to happen to 2001.

I've got a peculiar weakness for criminals and artists. Neither takes life as it is. Any tragic story has to be in conflict with things as they are.

Bad films gave me the courage to try making a movie

The world's religions, for all their parochialism, did supply a kind of consolation for this great ache. This shattering recognition of our mortality is at the root of far more mental illness than I suspect even psychiatrists are aware.

If it can be written, or thought, it can be filmed.

The destruction of this planet would have no significance on a cosmic scale.

If you can talk brilliantly about a problem