School of Faith's First Thursdays

People, both young and old, take all kinds of substances for all kinds of reasons, but usually to change the way they feel. Three common examples of substances are alcohol, antidepressants, and marijuana. What is the Catholic viewpoint on all of these substances? Are they all morally the same, or are there significant differences? To understand substances, we have to understand our feelings: why we have them, and how we should cultivate them.