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Comment by cwzwarich | Hacker News Reader

> I'll refrain from pulling out the old Alan Kay quotation in which he (the father of the term "object oriented") identifies Lisp and Smalltalk as the only two OO languages that he's aware of.

I think he was referring to Lisp in general in that quotation, not CLOS, although I remember glowing praise from him regarding The Art of the Metaobject Protocol.

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This is how i remembered it too. I thought he said something along the lines of lisp and smalltalk are the only two languages i am aware you can do OOP in. I tried to find this and couldn't.

And OOP here means these two things from Kay: (i)'In computer terms, Smalltalk is a recursion on the notion of computer itself. Instead of dividing "computer stuff" into things each less strong than the whole--like data structures, procedures, and functions which are the usual paraphernalia of programming languages--each Smalltalk object is a recursion on the entire possibilities of the computer.'

(ii) "Four techniques used together--persistent state, polymorphism, instantiation, and methods-as-goals for the object--account for much of the power."

i, ii are from http://www.smalltalk.org/smalltalk/TheEarlyHistoryOfSmalltal...

I think I found the source of the original quote here:

http://www.purl.org/stefan_ram/pub/doc_kay_oop_en

Yep, this is at least what I thought the commenter was referring to. Thanks!

> each Smalltalk object is a recursion on the entire possibilities of the computer.

So it's like a lambda expression. Except that:

1. OOP was invented 35 years later.

2. OOP is not based on the mathematical concept of the function, which is (arguably) the most successful idea ever dreamed up by (not as arguably) some of the smartest human beings ever to live.

3. Objects are lies. An object that calls itself a COW is not a cow; a function that calls itself SEND-COWS-TO-MONTANA really does send the cows to Montana.

Ergo OOP=dumb. What am I missing?

I'm curious why "an object that calls itself a COW is not a cow" yet "a function that calls itself SEND-COWS-TO-MONTANA really does"? Both are merely abstractions over ideas, no? One over the idea of a thing, one over the idea of doing something.

I think the idea is that domain logic is encapsulated in functions, while the objects themselves only contain metadata. So if you have an class of objects named 'COW', then the objects themselves will contain information about cows. If you simply delete the object, the cow will still exist.

However, if you run a function called, "slaughter_cow", then that should actually do something, maybe it will mark that cow for slaughter. Running functions should have real-world effects, directly manipulating data objects won't. (except maybe to cause confusion)

But this really just falls into the "no true Scottsman" fallacy, doesn't it? I mean, running a function called "slaughter_cow" that will only "mark that cow for slaughter" it is misnamed in some sense. Same for any function. Unless what you are doing is fully abstract in the first place, than any abstraction over it will in many senses be a lie.

The worker who got the message on the screen slaughters the cow, how can you not consider the worker and his process part of the code as well?

>3. Objects are lies. An object that calls itself a COW is not a cow; a function that calls itself SEND-COWS-TO-MONTANA really does send the cows to Montana.

Err, no it doesn't. Both are manipulating symbols (names), not actual cows.

That's how we can have games like Sim City that don't cost trillions of dollars to play.

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