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Recursive Functions of Symbolic Expressions Computation by Machine (1960)

www-formal.stanford.edu

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Re: Recursive Functions of Symbolic Expressions Computation by Machine (1960)

#6

Post by adrian_b »

rluoy wrote: post #2

always wonder where is part II.

This text, with minor, mostly typographical, differences had been previously published internally as "MIT AI Lab. AI Memo No. 8" in March 1959.

Two other earlier publications by McCarthy include various very important innovations, e.g. the conditional expressions in "AI Memo No. 1" (September 1958) and the "select" expressions (i.e. what are now named as "case" or "switch") in "AI Memo No. 4" (October 1958).

The text published in CACM in 1960 is the conclusion of the memos written by McCarthy between 1958-09 and 1959-03, when most of the ideas on which LISP is based have been conceived.

The "cond" and "select" expressions and the McCarthy "and" and McCarthy "or" expressions (i.e. C language && and ||) were not only new at that time, but they were much more convenient than the means used for expressing conditional execution in most later programming languages, which had various weird restrictions or peculiar syntax, for no good reason.

Re: Recursive Functions of Symbolic Expressions Computation by Machine (1960)

#7

Post by lispm »

At the same time (1960) there was already a Programmer‘s Manual for Lisp 1. Lisp then had a real implementation with a lot novel stuff like garbage collection, resumeable memory images, code as data, etc.

http://bitsavers.org/pdf/mit/rle_lisp/LISP_I_Programmers_Man...

Re: Recursive Functions of Symbolic Expressions Computation by Machine (1960)

#8

Post by kragen »

adrian_b wrote: post #6
rluoy wrote: post #2

always wonder where is part II.

This text, with minor, mostly typographical, differences had been previously published internally as "MIT AI Lab. AI Memo No. 8" in March 1959. Two other earlier publications by McCarthy include various very important innovations, e.g. the conditional expressions in "AI Memo No. 1" (September 1958) and the "select" expressions (i.e. what are now named as "case" or "switch") in "AI Memo No. 4" (October 1958). The text…

Thanks, this is great!

Re: Recursive Functions of Symbolic Expressions Computation by Machine (1960)

#9

Post by quesomaster9000 »

user3939382 wrote: post #5

I wish my formal math was stronger. I've been programming for 30 years but once a paper I'm reading starts using math notation I can't parse 90% of it and I'm lost.

The notation used is almost all explicitly defined or can be trivially derived by reading the descriptions provided, aside from cardinality e.g. |x^2 - a| which is assumed to be common knowledge.

Everything else is very simple pseudocode albeit with use of a few Greek letters or symbols, so I could hardly call this inaccessible to somebody who has been programming for 30 years...

Re: Recursive Functions of Symbolic Expressions Computation by Machine (1960)

#10

Post by user3939382 »

quesomaster9000 wrote: post #9
user3939382 wrote: post #5

I wish my formal math was stronger. I've been programming for 30 years but once a paper I'm reading starts using math notation I can't parse 90% of it and I'm lost.

The notation used is almost all explicitly defined or can be trivially derived by reading the descriptions provided, aside from cardinality e.g. |x^2 - a| which is assumed to be common knowledge. Everything else is very simple pseudocode albeit with use of a few Greek letters or symbols, so I could hardly call this inaccessible to somebody who has been programming for 30 years...

So, you're arguing that this: https://www-formal.stanford.edu/jmc/recursive/img242.png and this https://www-formal.stanford.edu/jmc/recursive/img66.png

are accessible with common knowledge to someone with programming experience but without a background in mathematics?

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