Psychologia Empirica

are inherent in the human mind; from these it is permitted to abstract general principles concerning every being that has a certain similarity to the soul, sufficient, that is, to constitute a certain genus (§. 710 Log.), that is to say, concerning Spirit in general. Wherefore, since God is also a Spirit, as will be demonstrated in natural theology, those principles can also be applied to Him (§. 346 Log.). Empirical psychology therefore provides principles to natural theology.

From this it is understood that natural theology must labor under many defects unless empirical psychology has been properly cultivated. The more profoundly you have occupied yourself with the latter, the more abundant light you will experience in the former. For the notions of divine attributes become distinct and determinate, and hence useful for reasoning: a fact which has manifold use not only in all practical philosophy and experimental natural theology, but even in revealed theology itself.

Use in practical philosophy.

Empirical psychology provides principles to practical philosophy. We have already given a demonstration (§. 92 Disc. prælim.), when we showed that practical philosophy must seek its principles from Metaphysics if everything in it is to be demonstrated: see it, therefore, in that place.

There is surely no other reason for the neglect of empirical psychology than that, especially in Ethics, the practice of cultivating virtues and shunning vices has been completely abandoned. For whatever can be said regarding this returns to the determination of the appetite: yet all perceptions whatsoever influence the determination of the appetite. Wherefore, the principles which are established in psychology concerning the determination of the appetite are transferred to special cases in Ethics. The entire philosophy of morals assumes a far different appearance when it is illuminated by the light of psychology, and only then can a certain judgment be made as to how far virtues are within one's power and what things keep us from their cultivation. Indeed, the things which we have established concerning moral philosophy can and ought to be applied to moral theology itself. The books that are written on this subject will not be freed from sterility unless those who are skilled in psychology turn their minds to reducing it to a system: this is a thing which not by simple