He who joyfully marches to music in rank and file has already earned my contempt. He has been given a large brain by mistake, since for him the spinal cord would suffice.

The whole of science is nothing more than a refinement of everyday thinking.

The world as we have created it is a process of our thinking. It cannot be changed without changing our thinking.

Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.

Paper is to write things down that we need to remember. Our brains are used to think.

This truth may be unfashionable, unpalatable, no doubt unpopular, but, if it is the truth, the story of mankind shows that war was universal and unceasing for millions of years before armaments were invented or armies organized. Indeed, the lucid intervals of peace and order only occurred in human history after armaments in the hands of strong governments have come into being, and civilization in every age has been nursed only in cradles guarded by superior weapons and superior discipline.