Nicomachean Ethics

There's a lot of fairly useful stuff in here, however, a lot of it's also fairly obvious (I hope). Book 2 was probably the most useful for me. The other books have very good explanations of concepts, but I didn't really need them so I quickly lost interest.

Over all this is a great into to philosophy but if you're slightly more seasoned (especial with the subject's Aristotle covers) it might be rather boring.

It took me so long to read but I regret nothing. The original self help/build better habits book. Aristotle bringing the reality to the idealised concepts of Plato.

Aristotle really understands the need to cultivate the habits of a good person before you can even become a good person, which is the kind of deep understanding of human nature I thoroughly appreciate. People aren't innately good or bad but they do have a gut that has the capacity to become good, you want to spend your life cultivating your gut feeling to be the right feeling.

He also has a nice ongoing thread on the need for unity within oneself, how each part of you is reflected in even the smallest actions you take, so you need to strive to achieve consistency across all your own selves. If you want to be whole you need to make sure every part of you lines up and if it doesn't then build the habits to hopefully learn to get there.

In summary:
Aristotle = a united gut