Since a given system can never of its own accord go over into another equally probable state but into a more probable one, it is likewise impossible to construct a system of bodies that after traversing various states returns periodically to its original state, that is a perpetual motion machine.

To go straight to the deepest depth, I went for Hegel; what unclear thoughtless flow of words I was to find there! My unlucky star led me from Hegel to Schopenhauer . . . Even in Kant there were many things that I could grasp so little that given his general acuity of mind I almost suspected that he was pulling the reader's leg or was even an imposter.

The general struggle for existence of animate beings is not a struggle for raw materials, these for organisms are air water & soil, all abundantly available, nor for energy which exists in plenty in the sun and any hot body in the form of heat, but rather a struggle for entropy, which becomes available through the transition of energy from the hot sun to the cold earth.

In my view all salvation for philosophy may be expected to come from Darwin's theory

Nothing is more practical than a good theory.

The most ordinary things are to philosophy a source of insoluble puzzles. With infinite ingenuity it constructs a concept of space or time and then finds it absolutely impossible that there be objects in this space or that processes occur during this time . . . the source of this kind of logic lies in excessive confidence in the so-called laws of thought.

Bring forward what is true, Write it so that it is clear, Defend it to your last breath!