I will not go so far as to say that to construct a history of thought without profound study of the mathematical ideas of successive epochs is like omitting Hamlet from the play which is named after him. That would be claiming too much. But it is certainly analogous to cutting out the part of Ophelia. This simile is singularly exact. For Ophelia is quite essential to the play, she is very charming . . . and a little mad.

Inventive genius requires pleasurable mental activity as a condition for its vigorous exercise

As society is now constituted, a literal adherence to the moral precepts scattered throughout the Gospels would mean sudden death.

Thus the negative perception is the triumph of consciousness.

...the only simplicity to be trusted is the simplicity to be found on the far side of complexity.

With the sense of sight, the idea communicates the emotion, whereas, with sound, the emotion communicates the idea, which is more direct and therefore more powerful.

The study of mathematics is apt to commence in disappointment... We are told that by its aid the stars are weighed and the billions of molecules in a drop of water are counted. Yet, like the ghost of Hamlet's father, this great science eludes the efforts of our mental weapons to grasp it.