Again, as we only really know when we know a thing as it is, that is, when our knowledge is true, the end of philosophy of science may be said to be Truth: hence philosophical or scientific Method will be a procedure so regulated as to enable the seeker to reach Truth.
It is thus that Descartes makes True Knowledge (vera cognitio), or Truth, the end of philosophical or scientific Method.
The mind, in proceeding by Method, while it manifests, likewise concentrates its activity. It seeks through the action of the faculties of knowledge specially directed, more perfect knowledge than is passively afforded in the spontaneous presentations of sense and self-consciousness. The activity of the faculties of knowledge is concentrated on objects, and is only manifested in accordance with certain rules. The cognitive power, by being thus limited to a determinate channel, is prevented from being wasted or thrown away in irregular exercise. The activity of the mind is subordinated to the realization of a given end; the mind itself has another rule than its own impetuosity. Descartes, therefore, to reach truth, and for the right conduct of the mind, that is, to prevent it from wasting its powers in capricious activity, instituted a Method.
Such is the end, and such the need of Method. It will be necessary, however, in the fourth place, to show more particularly the nature of the Method of Descartes; and, first, of the Method in its prior half.
