I got up this morning at 6:10am after going to sleep at 12:45am. I was awakened once during the night. My heart rate was 61 beats per minute. My blood pressure, 127 over 74. I had zero minutes of exercise yesterday, so my maximum heart rate during exercise wasn't calculated. I had about 600 milligrams of caffeine, zero of alcohol. And my score on the Narcissism Personality Index, or the NPI-16, is a reassuring 0.31.

We know that numbers are useful for us when we advertise, manage, govern, search. I'm going to talk about how they're useful when we reflect, learn, remember, and want to improve. A few year ago, Kevin Kelly, my partner, and I noticed that people were subjecting themselves to regimes of quantitative measurement and self-tracking that went far beyond the ordinary, familiar habits such as stepping on a scale every day. People were tracking their food via Twitter, their kids' diapers on their iPhone. They were making detailed journals of their spending, their mood, their symptoms, their treatments.

Now, we know some of the technological facts that are driving this change in our lifestyle -- the uptake and diffusion of mobile devices, the exponential improvement in data storage and data processing, and the remarkable improvement in human biometric sensors. This little black dot there is a 3D accelerometer. It tracks your movement through space. It is, as you can see, very small and also very cheap. They're now down to well under a dollar a piece, and they're going into all kinds of devices. But what's interesting is the incredible detailed information that you can get from just one sensor like this. This kind of sensor is in the hit biometric device -- among early adopters at the moment -- the Fitbit. This tracks your activity and also your sleep. It has just that sensor in it.

You're probably familiar with the Nike+ system. I just put it up because that little blue dot is the sensor. It's really just a pressure sensor like the kind that's in a doorbell. And Nike knows how to get your pace and and distance from just that sensor. This is the strap that people use to transmit heart-rate data to their Nike+ system.

This is a beautiful, new device that gives you detailed sleep tracking data, not just whether you're asleep or awake, but also your phase of sleep -- deep sleep, light sleep, REM sleep. The sensor is just a little strip of metal in that headband there. The rest of it is the bedside console. Just for reference, this is a sleep tracking system from just a few years ago -- I mean, really until now. And this is the sleep tracking system of today.

This just was presented at a health care conference in D.C. Most of what you see there is an asthma inhaler, but the top is a very small GPS transceiver, which gives you the date and location of an asthma incident, giving you a new awareness of your vulnerability in relation to time and environmental factors.

Now, we know that new tools are changing our sense of self in the world -- these tiny sensors that gather data in nature, the ubiquitous computing that allows that data to be understood and used, and of course the social networks that allow people to collaborate and contribute. But we think of these tools as pointing outward, as windows, and I'd just like to invite you to think of them as also turning inward and becoming mirrors. So when we think about using them to get some systematic improvement, we also think about how they can be useful for self-improvement, for self-discovery, self-awareness, self-knowledge.

Here's a biometric device: a pair of Apple Earbuds. Last year, Apple filed some patents to get blood oxygenation, heart rate and body temperature via the Earbuds. What is this for? What should it be for? Some people will say it's for biometric security. Some people will say it's for public health research. Some people will say it's for avant-garde marketing research. I'd like to tell you that it's also for self-knowledge. And the self isn't the only thing; it's not even most things. The self is just our operation center, our consciousness, our moral compass. So, if we want to act more effectively in the world, we have to get to know ourselves better.

Thank you.