(This is not an exhaustive list, of course.)
1: How the Beatles wrote so much awesome music that I love.
2: How people can actually believe what PETA advocates. I'm all for animal welfare, but these people are sacrificing human welfare to save cows from being eaten. Cows are dumb and yummy. Clearly made to be eaten. Someone else's blog on this topic
3: Why the weather can make people happy or sad. We really should be past that as a species by now....
4: Why people are willing to "settle". Theoretically we should be constantly striving towards a state of ecstasy or something. I suppose that's where drugs come in. It's hard to accomplish anything when you're ecstatic.
5: Why people get flustered when they get presents but can't give one back. Settle down. If I were expecting something back I would call it a loan or a trade or a sale, not a gift. So shush and take it. :P
6: How trees make me so frekken happy. Or puddles. They're just so inherently beautiful and soothing and so forth.
7: One-down-manship. Like you got your wisdom teeth pulled? Two? Oh, well I got FOUR pulled and it HURT more and I'm so much cooler. A comedian's take on this.
8: "Lucky" or "special" numbers like 7 or 3 or 12 or even 13.
Eight is a good list. Enjoy.