[Haskell-cafe] Re: Memoization

[Andrew Coppin]

Tony Morris wrote:
>> You managed to type ∀  but you couldn't find ⊥ ?
>>
>> OOC, can anybody tell me what ∀ actually means anyway?
>>     
>
> It is called the 'universal quantifier' and means "for all". It is often
> used implicitly in natural language. e.g. "cars are red" can be expanded
> to "[for all elements of the set of cars] cars [all elements of the set]
> are red". This statement can be formally expressed (though i won't for now).
>
> The universal quantifier, although most often used implicitly in natural
> language, is most often used explicitly in formal logic.
>
> You might also be interested in knowing of the "existential quantifier"
> which means "there exists". If I said "there exists a car [an element
> from the set of all cars] that is blue", then I have refuted the earlier
> logical proposition (that cars are red).
>
> The existential quantifier looks like a backward capital E
> ∃
>
> Look up "first-order logic" if you're interested in learning more about
> this topic.
>   

I see...

I do recall that GHC has some weird extension called "existential 
quantification", which makes absolutely no sense at all. So I looked up 
the term on Wikipedia, which says "see predicate logic". So I looked up 
predicate logic, which says it's an extension of "propositional logic", 
so I looked that up... and at this point I became increadibly confused! LOL.

> PS: What does OOC stand for? Out Of Curiosity?
>   

Indeed yes.