Nature does nothing without purpose or uselessly.

A cloudy day or a little sunshine have as great an influence on many constitutions as the most recent blessings or misfortunes.

Should the whole frame of nature round him break, In ruin and confusion hurled, He, unconcerned, would hear the mighty crack, And stand secure amidst a falling world.

There is not, in my opinion, anything more mysterious in nature than this instinct in animals, which thus rise above reason, and yet fall infinitely short of it.

Nature delights in the most plain and simple diet.