The doubter is a true man of science: he doubts only himself and his interpretations, but he believes in science.

The doubter is a true man of science: he doubts only himself and his interpretations, but he believes in science.

We achieve more than we know. We know more than we understand. We understand more than we can explain.

A man of science rises ever, in seeking truth; and if he never finds it in its wholeness, he discovers nevertheless very significant fragments; and these fragments of universal truth are precisely what constitutes science.

Men who have excessive faith in their theories ... make poor observations, because they choose among the results of their experiments only what suits their object, neglecting whatever is unrelated to it and carefully setting aside everything which might tend toward the idea they wish to combat

Well-observed facts, though brought to light by passing theories, will never die; they are the material on which alone the house of science will at last be built.

Now, a living organism is nothing but a wonderful machine endowed with the most marvellous properties and set going by means of the most complex and delicate mechanism.