There are two men in each one of us: the scientist, he who starts with a clear field and desires to rise to the knowledge of Nature through observations, experimentation and reasoning, and the man of sentiment, the man of belief, the man who mourns his dead children, and who cannot, alas, prove that he will see them again, but who believes that he will, and lives in the hope – the man who will not die like a vibrio, but who feels that the force that is within him cannot die.

The Greeks bequeathed to us one of the most beautiful words in our language--the word 'enthusiasm'--en theos--a god within. The grandeur of human actions is measured by the inspiration from which they spring. Happy is he who bears a god within, and who obeys it.

The role of the infinitely small in nature is infinitely great.

My opinion - nay more, my conviction - is that, in the present state of science, as you rightly say, spontaneous generation is a chimera; and it would be impossible for you to contradict me, for my experiments all stand forth to prove that spontaneous generation is a chimera.

Every chemical substance, whether natural or artificial, falls into one of two major categories, according to the spatial characteristic of its form. The distinction is between those substances that have a plane of symmetry and those that do not. The former belong to the mineral, the latter to the living world.

It is not the germs we need worry about. It is our inner terrain.

These three things-work, will, success-fill human existences. Will opens the door to success, both brilliant and happy. Work passes these doors, and at the end of the journey success comes in to crown one's efforts.