What are you most basic principles for life?

So, I've been chatting with my buddies lately, and it's turned into a bunch of debates about right and wrong. I think I have a pretty solid moral compass, I'm not bragging haha, but most people I know can't really explain why something's right or wrong without getting all circular or contradicting themselves.

So, how do you figure out what to do? No judgment, just curious. I'll share my thoughts below.

Thanks!

Edit: Oh, all you lil' philosophers have brought me a cornicopia of thoughts and ideas. I'm going to take my time responding, I'm like Treebeard, never wanna be hasty.