ticipating in it himself. He insists on quitting fruitless speculation and introducing the method of experience, induction, in every department of knowledge,—in the mental sciences as well as in the natural sciences. In the Novum Organon (1620) he examines the reasons why the sciences are inadequate and describes the inductive method. In the De Dignitate et Augmentis Scientiarum (1623) he presents a sketch of the actual state of the sciences and proceeds to show, frequently in a most brilliant manner, the gaps which still remain to be filled.
If a man would understand nature correctly, he must first of all reduce himself to a blank tablet. No one can enter the kingdom of nature except as a little child. But we are all hindered to a greater or less degree by various illusions, both native and acquired (Idola mentis). These may be divided into four classes. The first class, having its origin in human nature, is common to all mankind (Idola tribus). This is why we are constantly disposed to regard things from the viewpoint of their relation and their similarity to ourselves, rather than from the viewpoint of their true place in the general order of the universe—ex analogia hominis instead of ex analogia universi. We assume a greater degree of order and simplicity in things than the facts justify. We discover teleologic causes in nature because our own actions reveal such causes. The second class rests on individual peculiarity (Idola specus; every one interprets nature from the viewpoint of his own cave). This accounts for the fact that some minds are more impressed by the differences of things, whilst others are disposed to emphasize their resemblances. Some are constantly striving to analyze and reduce things to their elements; others are engrossed with