In a crystal we have clear evidence of the existence of a formative life principle, and though we cannot understand the life of a crystal, it is nonetheless a living being
The history of science can be viewed as the recasting of phenomena that were once thought to be accidents as phenomena that can be understood in terms of fundamental causes and principles.
Love requires that true education should be easily accessible to all and should be of use to every villager in this daily life. The emphasis laid on the principle of spending every minute of one's life usefully is the best education for citizenship.
The fourfold root of the principle of sufficent reason is "Anything perceived has a cause. All conclusions have premises. All effects have causes. All actions have motives.
There are some with whom we may study in common, but we shall find them unable to go along with us to principles. Perhaps we may go on with them to principles, but we shall find them unable to get established in those along with us. Or if we may get so established along with them, we shall find them unable to weigh occurring events along with us.
Capitalism justified itself and was adopted as an economic principle on the express ground that it provides selfish motives for doing good, and that human beings will do nothing except for selfish motives
Nature herself, as has been often said, requires that we should be able, not only to work well, but to use leisure well; for, as I must repeat once again, the first principle of all action is leisure. Both are required, but leisure is better than occupation and is its end.