Person of Interest2011

Harold Finch:
Pi. Can any of you tell me what it means? [There's no response from the class] I'll settle for an intelligent question here.

Lily Williams:
My friend has a question, Mr. Swift. "What is any of this good for, and when would we ever use it?"

Harold Finch:
Let me show you. Pi, the ratio of the circumference of a circle to its diameter, and this is just the beginning; it keeps on going, forever, without ever repeating. Which means that contained within this string of decimals, is every single other number. Your birthdate, combination to your locker, your social security number, it's all in there, somewhere. And if you convert these decimals into letters, you would have every word that ever existed in every possible combination; the first syllable you spoke as a baby, the name of your latest crush, your entire life story from beginning to end, everything we ever say or do; all of the world's infinite possibilities rest within this one simple circle. Now what you do with that information; what it's good for, well that would be up to you.