Again, the definition of passions of the soul is this: Passion is a sensible activity of the appetitive faculty, depending on the presentation to the mind of something good or bad. Or in other words, passion is an irrational activity of the soul, resulting from the notion of something good or bad. For the notion of something good results in desire, and the notion of something bad results in anger. But passion considered as a class, that is, passion in general, is defined as a movement in one thing caused by another. Energy, on the other hand, is a drastic movement, and by “drastic” is meant that which is moved of itself. Thus, anger is the energy manifested by the part of the soul where anger resides, whereas passion involves the two divisions of the soul, and in addition the whole body when it is forcibly impelled to action by anger. For there has been caused movement in one thing caused by another, and this is called passion.