In a world filled with hate, we must still dare to hope. In a world filled with anger, we must still dare to comfort. In a world filled with despair, we must still dare to dream. And in a world filled with distrust, we must still dare to believe.

The mind is a system of interrelated processes.

The human mind is a set of information-processing machines that were designed by natural selection to solve adaptive problems faced by our hunter-gatherer ancestors.

在数学中，你不是理解事物，你只是习惯了它们。