101:3.5

As pleasure and pain are, therefore, two growths out of the body and the soul, so there are many offshoots of these emotions. Reasoning, the universal farmer, purging and pruning each of these, tying up, watering, and transplanting, in every way improves the materials of the morals and affections. For reasoning is the leader of the virtues, but it is the sole ruler of the emotions. Observe then first, through the very things which stand in the way of temperance, that reasoning is absolute ruler of the emotions.

What is mankind, and what purpose do they serve? What is their good, and what is their evil?

As I am going to demonstrate a most philosophical proposition, namely, that religious reasoning is absolute master of the emotions. I would willingly advise you to give the utmost heed to philosophy. For reason is necessary to everyone as a step to science. In addition, it embraces the praise of self-control, the highest virtue. If, then, reasoning appears to hold the mastery over the emotions which stand in the way of temperance, such as gluttony and lust, it surely also and manifestly rules over the affections which are contrary to justice, such as malice, and of those which are hindrances to courage, such as wrath, pain, and fear. Perhaps some may ask, “How is it, then, that reasoning, if it rules the emotions, isn’t also master of forgetfulness and ignorance?” They attempt a ridiculous argument. For reasoning does not rule over its own emotions, but over those that are contrary to justice, courage, temperance, and self-control; and yet over these, so as to withstand, without destroying them.