“a law is but a deduction from experience and experiment, and therefore laws must conform with historical facts, not facts with law.”

“All rational knowledge is either material, and concerns some objects, or formal, and is occupied only with the form of understanding and reason itself and with the universal rules of thinking, without regard to distinctions among objects. formal philosophy is called logic. Material philosophy, however, which has to do with definite object objects and the laws to which they are subject, is divided into two parts. This is because these laws are either laws of nature or laws of freedom. The science of the former is called physics, and that of the latter ethics. The former is also called theory of nature and the latter theory of morals.”

“act as if the maxim of your action were to become by your will a general law of nature.”

“Act only according to that maxim whereby you can at the same time will that it should become a universal law.”

“Seek not the favor of the multitude; it is seldom got by honest and lawful means. But seek the testimony of few; and number not voices, but weigh them.”

“But although all our knowledge begins with experience, it does not follow that it arises from experience.”

“Two things fill the mind with ever new and increasing admiration and awe, the oftener and more steadily we reflect on them: the starry heavens above and the moral law within.”