If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress.
As Arkwright and Whitney were the demi-gods of cotton, so prolific Time will yet bring an inventor to every plant. There is not a property in nature but a mind is born to seek and find it.
Remember the Three Princes of Serendip who went out looking for treasure? They didn't find what they were looking for, but they kept finding things just as valuable. That's serendipity, and our business [drugs] is full of it.
Evolution is the law of policies: Darwin said it, Socrates endorsed it, Cuvier proved it and established it for all time in his paper on The Survival of the Fittest. These are illustrious names, this is a mighty doctrine: nothing can ever remove it from its firm base, nothing dissolve it, but evolution.
The lessons of science should be experimental also. The sight of a planet through a telescope is worth all the course on astronomy; the shock of the electric spark in the elbow outvalues all theories; the taste of the nitrous oxide, the firing of an artificial volcano, are better than volumes of chemistry.
But what is classification but the perceiving that these objects are not chaotic, and are not foreign, but have a law which is also the law of the human mind?
Lo! the poor Indian! whose untutor'd mind
Sees God in clouds, or hears him in the wind;
His soul proud Science never taught to stray
Far as the solar walk or milky way.
There rolls the deep where grew the tree. O earth, what changes hast thou seen! There where the long street roars, hath been The stillness of the central sea. The hills are shadows, and they flow From form to form, and nothing stands; They melt like mist, the solid lands, Like clouds they shape themselves and go.