"How tardily men arrive at any result! how tardily they pass from it to another! The crystal sphere of thought is as concentrical as the geological structure of the globe. As our soils and rocks lie in strata, concentric strata, so do all men's thinkings run laterally, never vertically. Here comes by a great inquisitor with auger and plumb-line, and will bore an Artesian well through our conventions and theories, and pierce to the core of things. But as soon as he probes the crust, behold gimlet, plumb-line, and philosopher take a lateral direction, in spite of all resistance, as if some strong wind took everything off its feet, and if you come month after month to see what progress our reformer has made, not an inch has he pierced, you still find him with new words in the old place, floating about in new parts of the same old vein or crust. The new book says, 'I will give you the key to nature,' and we expect to go like a thunderbolt to the centre. But the thunder is a surface phenomenon, makes a skin-deep cut, and so does the sage. The wedge turns out to be a rocket. Thus a man lasts but a very little while, for his monomania becomes insupportably tedious in a few months. It is so with every book and person: and yet - and yet - we do not take up a new book, or meet a new man, without a pulse-beat of expectation. And this invincible hope of a more adequate interpreter is the sure prediction of his advent."
I particularly like The wedge turns out to be a rocket. The whole jing-bang here.