When it was suggested to Pasteur that many of his great achievements depended on luck, he replied - I'm sure with more than a little irritation - 'In the field of observation in science, fortune only favours the prepared mind.' It is not by chance that it is always the great scientists who have the luck.

It is not birth, marriage, or death, but gastrulation which is truly the most important time in your life.

Reliable scientific knowledge is value free and has no moral or ethical value. Science tells us how the world is. ... Dangers and ethical issue arise only when science is applied as technology.

Depression is sadness gone wrong

I regard it as ethically unacceptable and impractical to censor any aspect of trying to understand the nature of our world.

Both Newton and Darwin were driven by the data and were forced to recognize that they couldn't explain everything. It may be a characteristic of great scientists to know what to accept and what to leave out.

The image of the disinterested, dispassionate scientist is no less false than that of the mad scientist who is willing to destroy the world for knowledge.