Fortune favors the prepared mind.
It is surmounting difficulties that makes heroes.
Do not let yourself be tainted with a barren skepticism.
In the fields of observation, chance favors only the prepared mind.
There are no such things as applied sciences, only applications of science.
Let me tell you the secret that has led me to my goal. My strength lies solely in my tenacity.
Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world.
When I approach a child, he inspires in me two sentiments; tenderness for what he is, and respect for what he may become.
Without theory, practice is but routine born of habit. Theory alone can bring forth and develop the spirit of inventions.