The theory is when we know how things work but they don't work. The practice one is when the things work but we don't know why. We have joined the theory and the practice: Now the things don't work anymore and we don't know why!
A person who never made a mistake, never has tried to make something new.
Equations are important to me, like politics to a president, even if an equation is something that remains in eternal.
One may say "the eternal mystery of the world is its comprehensibility".
Science cannot establish any purpose and nonetheless instil them into human beaings; science, there again, can give the means with which to reach certain aims. But those same aims are conceived by people with high ethical ideals.
I have no special talents. I am only passionately curious.
The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science.
Only a life lived for others is a life worthwhile.
The world is that disaster you see, not because of the troubles made by wrongdoer, but for the righteous' inactivity that they realize it and simply watch.
The important thing is not to stop questioning.