I read a lot of philosophy, and there is no part of philosophy that I enjoy more than the question of happiness. And why is this? Because I agree with Aristotle that happiness is the end or purpose of life. It is what we seek for its own sake. Ask anyone why they do anything, and their logic will eventually end with the statement that they are doing this to be happy.
The problem with Aristotle is that he really never tells us what happiness is. He comes to a logical dead end. I think Epicurus answered Aristotle's problem by defining happiness as pleasure. Religious people desire heaven or paradise which is always described as a place of immense and unending pleasure. The same is true of drug addicts, athletes, or what have you. They all seek some pleasure as their end.
Where Epicurus comes up short is that he defines pleasure as the absence of pain. The result is a prescription of simplicity, mild asceticism, and boredom. The reality is that pleasure is multiple. For some people, it is simply a case of getting drunk and getting laid. For the workaholic, it is simply a matter of performing labor that is satisfying. By looking at life, we must conclude that pleasure and happiness is not the same for everyone. This is probably a good thing since if it were I doubt any of us would be very happy. For instance, I find pleasure in listening to music, but I wouldn't have music if someone didn't find pleasure in creating it.
My viewpoint on this is a blending of Aristotle and Epicurus. I believe happiness comes from finding the things you enjoy doing and then just doing them. Happiness is the pleasure that comes from a life of productive activity. Activities such as drinking or screwing can be fun, but they have their limits. I also don't see the pleasure people derive from hurting others.
I think if Aristotle and Epicurus had gotten together that Aristotle would have simply worked out a taxonomy of pleasures. For instance, there is the pleasure that comes from friendship, the pleasure that comes from virtue, the pleasure that comes from hard work, etc. There are also the pleasures that sick fuckers like the Marquis de Sade or a child molester would have. Not all pleasures are equal or valid.
The pleasures I enjoy the most come from intellectual contemplation, aesthetic enjoyment, hard work, writing, and eating fatty foods. This brings us to the discussion of virtues and vices. My tentative theory is that a virtue is a legitimate pleasure while a vice is an illegitimate pleasure. What makes something a vice is that it causes harm to either yourself or to others. Vices are simply excesses while virtues are the means between these excesses.
This is fascinating stuff to me. By synthesizing these elements, we find that a truly happy life comes from a life of virtue which is simply moderation in all things. I think this stuff could make a great book. It is definitely something I intend to explore.