Some aspects of learning need to happen inside your comfort zone. Learning to stand up on the surfboard when it’s still high and dry on the sand. Learning the correct ski position while stationary at the bottom of the mountain. Learning how to write functional programs in javascript before you have the pressure of someone paying you to do it.

If you just do those bits, you might be learning at an intellectual level—but that isn’t real learning.

Real learning requires a whole bunch of things to happen outside your comfort zone. Learning how to stay standing on the board after you paddle into the wave and it begins to break behind you. Learning to ski a controlled turn when you’re staring down an impossibly steep slope with an equally impossibly breathtaking view. Learning to troubleshoot a program you’ve written for someone who has paid good money for something that should work and currently doesn’t.

The boundary of your comfort zone separates these two aspects of learning. To learn then, we simply need to tread back and forth over this boundary, in both directions—and to tread it so often that the boundary becomes indistinguishable. It’s the movement back and forth that obliterates the boundary.

That’s how learning works.