According to The Two Things, "For every subject, there are really only two things you really need to know. Everything else is the application of those two things, or just not important.”
Here are some examples,
The Two Things about Boxing:
2. Don't get hit.
The Two Things about World Conquest:
1. Divide and Conquer.
2. Never invade Russia in the winter.
For many more Two Things, click here.