I would give absolutely nothing for the theory of Natural Selection, if it requires miraculous additions at any one stage of descent.

You will be astonished to find how the whole mental disposition of your children changes with advancing years. A young child and the same when nearly grown, sometimes differ almost as much as do a caterpillar and butterfly.

Disbelief crept over me at a very slow rate, but at last it was complete.

Worms have played a more important part in the history of the world than humans would at first suppose.

The western nations of Europe, who now so immeasurably surpass their former savage progenitors, and stand at the summit of civilization, owe little or none of their superiority to direct inheritance from the old Greeks, though they owe much to the written works of that wonderful people.

Intelligence is based on how efficient a species became at doing the things they need to survive.

Among the scenes which are deeply impressed on my mind, none exceed in sublimity the primeval [tropical] forests, ... temples filled with the varied productions of the God of Nature. No one can stand in these solitudes unmoved, and not feel that there is more in man than the mere breath of his body.