It is the man of , eager to have his every opinion regenerated, his every idea rationalized, by drinking at the fountain of fact, and devoting all the energies of histo the cult of , not as he understands it, but as he does not yet understand it, that ought properly to be called a . To an earlier age knowledge was— merely that and nothing more; to us it is life and the . Emancipation from the bonds of , of one's own prepossessions, importunately sought at the hands of that rational power before which all must ultimately bow, — this is the characteristic that distinguishes all the great figures of nineteenth-century science from those of former periods.