He who is mistaken in an action which he sincerely believes to be right may be an enemy, but retains our esteem.

I wanted to see what no one had yet observed, even if I had to pay for this curiosity with my life.

[we see that] science is eminently perfectible, and that each theory has constantly to give way to a fresh one.

It is not new continents the earth needs, but new men.

What a big book, captain, might be made with all that is known!" "And what a much bigger book still with all that is not known!

Nature's creative power is far beyond man's instinct of destruction.

There is no more sagacious animal than the Icelandic horse. He is stopped by neither snow, nor storm, nor impassable roads, nor rocks, glaciers, or anything. He is courageous, sober, and surefooted. He never makes a false step, never shies. If there is a river or fjord to cross (and we shall meet with many) you will see him plunge in at once, just as if he were amphibious, and gain the opposite bank.