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Hofstadter on Lisp (1983)

(gist.github.com)
372 points Eric_WVGG | 5 comments | | HN request time: 0.204s | source
1. paulddraper ◴[] No.41870979[source]
> As you might expect, the value of the atom 1729 is the integer 1729, and this is permanent. (I am distinguishing here between the atom whose print name or pname is the four-digit string 1729, and the eternal Platonic essence that happens to be the sum of two cubes in two different ways - i.e., the number 1729.)

He is? What is the distinguishment he is making?

This writing styling is....interesting.

replies(3): >>41871040 #>>41871047 #>>41871222 #
2. WolfeReader ◴[] No.41871040[source]
The lisp atom 1729 is like a "constant" in a programming language, representing a particular arrangement of bits in lisp systems. The integer 1729 is a number that, in a mathematical sense, has always existed and will always exist regardless of computer systems.

While some atoms can be assigned values, the atom 1729 cannot be assigned any value other than the number 1729.

3. Y_Y ◴[] No.41871047[source]
An atom is something defined in the semantics of lisp and a part of the program, it will be represented as bits in the computer memory and as pixels on the screen. A number is a very general concept with many representations, on of which is as a lisp atom, and another could be a pile of 1729 kiwis. The kiwis and the code both represent the number, but they don't represent each other.
4. shrubble ◴[] No.41871222[source]
The use of 1729 would be known to people who know about Ramanujan: https://en.wikipedia.org/wiki/1729_(number)
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5. Y_Y ◴[] No.41872614[source]
Hey, that's the code to my safe!