There is no part of the country where in the summer you cannot get a sufficient supply of the best specimens. Teach your children to bring them in for themselves. Take your text from the brooks, not from the booksellers.

As long as men inquire, they will find opportunities to know more upon these topics than those who have gone before them, so inexhaustibly rich is nature in the innermost diversity of her treasures of beauty, order and intelligence.

I now never make the preparations for penetrating into some small province of nature hitherto undiscovered without breathing a prayer to the Being who hides His secrets from me only to allure me graciously on to the unfolding of them.

In Europe I have been accused of taking my scientific ideas from the Church. In America I have been called a heretic, because I will not let my church-going friends pat me on the head.

The study of Nature is intercourse with the highest mind. You should never trifle with Nature. At her lowest her works are the works of the highest powers, the highest something in the universe, in whichever way we look at it... This is the charm of Study from Nature itself; she brings us back to absolute truth wherever we wander.

I cannot afford to waste my time making money

Every great scientific truth goes through three states: first, people say it conflicts with the Bible; next, they say it has been discovered before; lastly, they say they always believed it.