Fulvio Di Blasi explains the ultimate difference between intellect and will according to Saint Thomas Aquinas.
The Altruism of the Will.
How can we distinguish the intellect from the will or, more generally, the cognitive powers of the soul from the appetitive powers?
One way to explain this difference is through the distinction between active and passive powers of the soul. The intellect and the cognitive powers in general are receptive in the sense that they receive data from the outside, like the eye receives colors and the ear sounds. In this sense, they are passive. The will and the appetites are active because they move toward the known object, like a dog at the sight or smell of food turns to eat.
Yet, the deepest and most comprehensive explanation of the difference between cognitive and appetitive powers requires an additional step, because even the cognitive powers, properly speaking, “appetite” or desire their object. On this point, St. Thomas Aquinas offers a reflection that Di Blasi expresses in terms of “altruism” of the appetitive power.
Dr. Fulvio Di Blasi is an internationally renowned scholar in the field of moral philosophy, natural law theory, and Thomistic philosophy. He is Founder and President of the Thomas International Project, President of the Thomas International Association in Italy, and Director of the Thomas International Center in Raleigh, NC.