instruere...inlustrare...delectare Disputations

Saturday, April 28, 2012

Acting Classes

At a very high level, actions and movements may be classified according to the answers to these two questions:
  1. Is the thing acting or moving itself in order to achieve some end?
  2. If so, is the end known by reason?
These questions partition actions and movements into three classes, each of which has its own appetite: the involuntary, when the thing moves due to a natural appetite that has no knowledge of the end; the imperfect voluntary, when the thing moves due to a sensitive appetite that desires some concrete good in response to something the thing apprehends through the senses; and the perfect voluntary or chosen, when the thing moves due to a rational appetite that desires some good understood as a good to be desired and obtained.

There are a couple of ways to contrast the classes with each other. The first question above makes the distinction between a thing moving knowing the end for which it moves -- in which case, the movement is voluntary and we say the thing is moving itself -- and not knowing -- involuntary, the thing isn't moving itself.

Another contrast is between necessary motion and free motion. According to St. Thomas, only the rational appetite -- better known as the will -- is free.

This, as you may know, is a contentious claim. In what sense is the human will free? And why isn't the sensitive appetite also free?