It seems that we only have control over two things in our life: the hours allotted to us, and the things we put our attention on in those hours. But that’s a fact that’s easy to miss.

We worry about how pretty we are. About how smart we are. About how kind we are. About what people think of us. And what we’re worth. But none of those things change the heart fact that we’ve only got control over our time and attention.

We can spend time and attention to get smarter. We can spend time and attention to work on being more kind, or fit, or to have a bigger bank account. We can spend it being entertained by the latest novels or the dumbest television. But fundamentally what we’re doing here is taking the time we’re given and spending it on the things we give our attention to.

Want to be more productive? Think seriously about where you’re actually putting your time and attention and where you’d feel most productive putting your time and attention. It seems almost comical in its simplicity, but that’s really all that productivity comes down to.

The heart of David Allen’s Getting Things Done, for example, is a study of why people are really bad about managing their time and attention and spend it in all the wrong places. When we’re not strategic, we can easily drain of our time and attention rehashing the same decisions over and over again rather than acting. Or when we make ourselves remember tasks to do, we waste energy (which is essentially the compound form of time and attention) on the act of remembering.

I’m ever more certain that all things that matter in life are stupidly simple. But that simple doesn’t mean easy. And the fact that productivity comes down to the decisions and stratagems that we use to decide how and where to use our energy seems to fit. You don’t get to make more time, and you may sometimes find it hard to control your attention. But realize that those two things are just about the only variables you really control and you’ll find yourself ahead of the game.