The only thing we truly have is time.
What follows from that:
First, we each have to figure out how we want to spend our time.
Then, we have to figure out how much money other people will pay us in exchange for our time.
Third, if we want to get rich, we have to figure out how to maximise that amount.
Fourth, in order to get wealthy, we have to figure out how to get other people to use their time to make you money.
Which makes me think: all we have is time, but the most important thing we can do is learn how to deal with other people.