Over the last few millennia we've invented a series of technologies - from the alphabet to the scroll to the codex, the printing press, photography, the computer, the smartphone - that have made it progressively easier and easier for us to externalize our memories, for us to essentially outsource this fundamental human capacity.

One trick, known as the journey method or 'memory palace,' is to conjure up a familiar space in the mind's eye, and then populate it with images of whatever it is you want to remember.

When you want to get good at something, how you spend your time practicing is far more important than the amount of time you spend.

If you were a medieval scholar reading a book, you knew that there was a reasonable likelihood you'd never see that particular text again, and so a high premium was placed on remembering what you read. You couldn't just pull a book off the shelf to consult it for a quote or an idea.

Our lives are the sum of our memories. How much are we willing to lose from our already short lives by … not paying attention?

It is forgetting, not remembering, that is the essence of what makes us human. To make sense of the world, we must filter it. "To think," Borges writes, "is to forget.

Many memory techniques involve creating unforgettable imagery, in your minds eye. Thats an act of imagination. Creating really weird imagery really quickly was the most fun part of my training to compete in the U.S. Memory Competition.