How to know when you're materialistic.
That's easy!
It's when nothing you have is good enough for you, but it still is good enough to make you think you're better than other people.

You'll see materialistic people in public everyday.
You just gotta laugh inside at them as you see their head swelling from their self made greatness.
You should only value the important things in life. Most of the important things have blood running through them.