The unknown is the largest need of the intellect.

They are ill discoverers that think there is no land, when they can see nothing but sea.

The atavistic urge toward danger persists and its satisfaction is called adventure.

Research is formalized curiosity. It is poking and prying with a purpose. 

I learned to make my mind large, as the universe is large, so that there is room for paradoxes.

One doesn’t discover new lands without consenting to lose sight of the shore for a very long time.

Nature has planted in our minds an insatiable desire to seek the truth.

There are truths that prove their discoverers witless.

One sees great things from the valley; only small things from the peak.

Every man takes the limits of his own field of vision for the limits of the world.