Science increases our power in proportion as it lowers our pride.

Those who do not know the torment of the unknown cannot have the joy of discovery.

A contemporary poet has characterized this sense of the personality of art and of the impersonality of science in these words,-'Art is myself; science is ourselves. '

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.

It is what we know already that often prevents us from learning.

In these researches I followed the principles of the experimental method that we have established, i.e., that, in presence of a well-noted, new fact which contradicts a theory, instead of keeping the theory and abandoning the fact, I should keep and study the fact, and I hastened to give up the theory.

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.