Recently started reading Switch, a book about how we react to change, I learned about the The Happiness Hypothesis by Jonathan Haidt. He's a psychologist and his analogy about the 2 different aspects of our behavior is very interesting. We have a logical/rational side which is known as the Rider, and emotional side dubbed the Elephant. As you might expect, the Rider is the one in control and guiding the Elephant. However, this is only an illusion because when both sides can't agree with each other, the Elephant is going to win most of the time. The Rider will be outmatched by the Elephant whenever there's a conflict between them.
This is a problem because the Elephant side of us is usually lazy and prefer instant gratifications. The Elephant is all about short term gain where the Rider prefer to analyze and plan for the future. But the Rider have it's own weakness where it usually spend too much time analyzing and end up doing nothing. The Rider gets analysis paralysis.
The book teaches you how to appeal to both the Elephant and the Rider to get change to happen. I think this applies to everything we do. Elephant is the source of energy where as the Rider is the one with the direction.
Passion without direction is useless. And so is direction without motivation. If you want to get things done, try your best to appeal to both the Elephant and the Rider.