Obvious(ly) misleading

This is my first post here. The first of many I hope!
Let's try this: please try to guess what I'm writing about. Can you do it? It's obvious! No? Really? Of course you can't. How could you?

It wasn't that obvious after all... I'm writing about what is obvious and what is not!
1 + 1 = 2. Obvious! That was really easy, everyone knows that!
Wait a moment... how do we know that 1 + 1 = 2? Maybe because we were told so. But what if everyone is wrong? 

Don't worry. Mathematicians worked out this question for us. I'm not going into details here, it doesn't really matter. What matters is that this question is a lot deeper than it seems. If you think about it, you'll end up asking yourself what a sum is, what a number is... those are tough questions.

Can you tell me what a number is? You kinda of know what it is... but do you know for sure? Is infinite a number?

Enough of mathematics already! What I'm trying to say is that there is nothing so obvious that it doesn't deserve a closer look. There is no obvious stuff!
Usually people use this word when they either don't know how to explain, or they don't want to deal with the details. The first case is a lot more common.

Why is the life of someone more important than the life of a cockroach? This is the kind of question people avoid, because the answer is obvious. Actually it's NOT obvious!

From now on, every time someone uses that word on you, think about it. Is it really that obvious?