If you want to live a memorable life, you have to be the kind of person who remembers to remember.

Now more than ever, as the role of memory in our culture erodes at a faster pace than ever before, we need to cultivate our ability to remember. Our memories make us who we are. They are the seat of our values and source of our character. Competing to see who can memorize more pages of poetry might seem beside the point, but it's about taking a stand against forgetfulness, and embracing primal capacities from which too many of us have became estrangedmemory training is not just for the sake of performing party tricks; it's about nurturing something profoundly and essentially human.

Just as we accumulate memories of facts by integrating them into a network, we accumulate life experiences by integrating them into a web of other chronological memories. The denser the web, the denser the experience of time.

I met with amnesiacs and savants, educators and scientists, to try to understand what memory is, why it works, why it sometimes doesn't, and what its potential might be.

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

With our blogs and tweets, digital cameras, and unlimited-gigabyte e-mail archives, participation in the online culture now means creating a trail of always present, ever searchable, unforgetting external memories that only grows as one ages.

Back when I lived in Brooklyn, I'd sometimes take the Q train all the way out to Coney Island and back, and work on my laptop. There's something about pushy New Yorkers looking over your shoulder that really makes you produce sentences.