Louis Pasteur Ideas Quotations

Worship the spirit of criticism. If reduced to itself it is not an awakener of ideas or a stimulant to great things, but, without it, everything is fallible; it always has the last word.

It is a matter of fact; I approached without a preconceived idea, too ready to declare, if the experiment had imposed upon me the confession, that there was a spontaneous generation, of which I am convinced today that those who assure it are blindfolded.

Preconceived ideas are like searchlights which illumine the path of the experimenter and serve him as a guide to interrogate nature. They become a danger only if he transforms them into fixed ideas-this is why I should like to see these profound words inscribed on the threshold of all the temples of science: 'The greatest derangement of the mind is to believe in something because one wishes it to be so.'