what I have said in regard to the universal faculty in man. It is obvious that this faculty must be the power, or seat, or place of necessary thinking, that is, of thoughts which we cannot help thinking, thoughts of which the opposites are pure nonsense; and in like manner it is obvious that the truths with which this faculty deals must be necessary truths, truths which cannot help being as they are, truths which cannot be otherwise than they are, and the opposites of which are pure nonsense. There is thus an objective necessity in truth, and a subjective necessity in thought, and the one of these corresponds to the other. For example, we say it is an objective necessary truth that two straight lines should not be capable of enclosing a space. And we say it is a subjective necessary thought that two straight lines should not be thought capable of enclosing a space. But what you have chiefly to attend to is, that wherever a necessary truth is apprehended, a truth which cannot be otherwise than it is, there the faculty of necessary truth, the universal faculty, comes into play, there necessary thinking takes place, there we think a thought which we cannot help thinking.
29. These considerations enable me to add something to my definition of philosophy, and to give it out in the following terms, which are the most definite, as well as the most complete, which I can at present devise. Philosophy is the pursuit of absolute truth, or of the absolutely real, that is, of the true and
