Sunday, July 1, 2012

Ikea shopping and λ-calculus

Yesterday I was at Ikea with a friend of mine (whose startup, Flockwire, has desks right beside mine), picking furniture for my first ever unfurnished apartment.

I was spending way too much time trying to pick the right shower curtain, when two thoughts simultaneously crossed my mind.

The first was a recent story I heard about why Alonzo Church picked the greek letter λ for his calculus. It is from Dana Scott's talk in the Turing Award webcast,
...but many years later I asked John Addison, Church's son-in-law if he would ask Church where the lambda came from. So he wrote him a post card [...] "Dear Prof Church, Russell had the iota operator, Hilbert had the epsilon operator, why in the world did you choose lambda for your operator?" So Church didn't write a letter, he just annotated the post card and sent it back, and he put in the margins, "Eeny, meeny, miny, moe."
The second was the following clip from Fight Club,

On one hand, a shower curtain is a shower curtain. There is really no difference between two shower curtains of a similar quality, just as the letter λ is no better or worse than any other greek letter. On the other hand, whichever shower curtain I pick will be sharing my bathroom for at least a year, so as silly as it sounds, I did want to choose one that "defined me as a person".

It's funny to imagine Church asking the question, "which greek letter best defines me as a person?" The letter Church chose is now attached to his name -- not for one year, not for two years, but indefinitely.

I ended up choosing the curtain by bringing two to checkout, and making the final decision under time pressure. It was much easier that way.

(It feels so strange, even blasphemous, comparing λ-calculus to my shower curtain.)

End of Entry