As the scene of life would be more the cold emptiness of space than the warm, dense atmosphere of planets, the advantage of containing no organic material at all, so as to be independent of both these conditions, would be increasingly felt.

The greater the man, the more he is soaked in the atmosphere of his time; only thus can he get a wide enough grasp of it to be able to change substantially the pattern of knowledge and action.

The region of the mysterious is rapidly shrinking.

The full area of ignorance is not mapped. We are at present only exploring the fringes.

The question of the origin of life is essentially speculative. We have to construct, by straightforward thinking on the basis of very few factual observations, a plausible and self-consistent picture of a process which must have occurred before any of the forms which are known to us in the fossil record could have existed.

The psychology of a complex mind must differ almost as much from that of a simple, mechanized mind as its psychology would from ours; because something that must underlie and perhaps be even greater than sex is involved.

Her [Rosalind Franklin] devotion to research showed itself at its finest in the last months of her life. Although stricken with an illness which she knew would be fatal, she continued to work right up to the end.