Worry is interest paid on trouble before it comes due.
Nature takes away any faculty that is not used.
Civilization is being poisoned by its own waste products.
Every institution not only carries within it the seeds of its own dissolution, but prepares the way for its most hated rival.
The greatest obstacle to progress is not man's inherited pugnacity, but his incorrigible tendency to parasitism.
Admiration for ourselves and our institutions is too often measured by our contempt and dislike for foreigners.