Nothing is so dangerous to the progress of the human mind than to assume that our views of science are ultimate, that there are no mysteries in nature, that our triumphs are complete and that there are no new worlds to conquer.

The well-mannered man never puts out his hand in greeting until a lady extends hers. This is a test of good breeding that is constantly applied. ... The first move in the direction of cordiality must come from the lady, the whole code of behaviour being based on the assumption that she is the social superior.

Fortunately science, like that nature to which it belongs, is neither limited by time nor by space. It belongs to the world, and is of no country and no age. The more we know, the more we feel our ignorance; the more we feel how much remains unknown.

Consistency in opinion is the slow poison of intellectual life, the destroyer of its vividness and energy.

This sentiment of self-contempt is a frequent one in young people of both sexes. Their valuation of themselves varies as much as the barometer, and is as much affected by outward causes.

Nature is beautiful, and you are in her bosom. That voice of comfort which speaks in the breezes of morning, may visit your mind, that the delightful influences which the green leaves, the blue sky, the moonbeams and clouds of the evening diffuse over the universe, may in their powers of soul-healing, visit your day visions, is my desire and hope.

Every discovery opens a new field for investigation of facts, shows us the imperfection of our theories. It has justly been said, that the greater the circle of light, the greater the boundary of darkness by which it is surrounded.