• Pau D. Anderson <paul.d.anderson.removethis comcast.andthis.net> Apr 07 2008
• Bill Baxter <dnewsgroup billbaxter.com> Apr 07 2008

Pau D. Anderson <paul.d.anderson.removethis comcast.andthis.net> writes:

Bill Baxter Wrote:

 
 Hmm, so would it be correct to say that monad is just another way to say 
 'impure function'?  It sounds like that's all you're saying.  So just 
 like we're going to have 'pure' to isolate the functional code in D, 
 functional languages have 'impure' functions that isolate the 
 procedural/stateful stuff.  They just happen to give those impure 
 functions a ridiculous name.
 
 Seriously why on earth are they called 'monads'?  Sounds like it derives 
 from "mono" meaning "one", like "triad" is a group of three things.  So 
 'monad' should mean a group of one thing I would thing.  Yet it means 
 "impure function".  Really odd.  I hate it when people give things 
 terrible non-descriptive names.  But maybe there's a rational explanantion?
 
 --bb


According to an online dictionary the word derives from the Latin monas as you
surmised. I think the meaning is more along the lines of unified or indivisible
rather than the number one:

n.
Philosophy. An indivisible, impenetrable unit of substance viewed as the basic
constituent element of physical reality in the metaphysics of Leibnitz.
Biology. A single-celled microorganism, especially a flagellate protozoan of
the genus Monas.
Chemistry. An atom or a radical with valence 1.
[Latin monas, monad-, unit, from Greek, from monos, single.]

Aren't elements in lisp called atoms?

According to another online source, Epicurus called the indivisible bits that
made up the world "monads" while Democritus famously called them "atoms". (In
ancient Greek, of course. English wasn't invented for at least twenty years
after Epicurus.)

So "monad" is just another word for "atom", a synonym used for the specifiic
meaning above, I guess.

Paul

Bill Baxter <dnewsgroup billbaxter.com> writes:

Pau D. Anderson wrote:
 Bill Baxter Wrote:
 
 Hmm, so would it be correct to say that monad is just another way to say 
 'impure function'?  It sounds like that's all you're saying.  So just 
 like we're going to have 'pure' to isolate the functional code in D, 
 functional languages have 'impure' functions that isolate the 
 procedural/stateful stuff.  They just happen to give those impure 
 functions a ridiculous name.

 Seriously why on earth are they called 'monads'?  Sounds like it derives 
 from "mono" meaning "one", like "triad" is a group of three things.  So 
 'monad' should mean a group of one thing I would thing.  Yet it means 
 "impure function".  Really odd.  I hate it when people give things 
 terrible non-descriptive names.  But maybe there's a rational explanantion?

 --bb


 According to an online dictionary the word derives from the Latin monas as you
surmised. I think the meaning is more along the lines of unified or indivisible
rather than the number one:
 
 n.
 Philosophy. An indivisible, impenetrable unit of substance viewed as the basic
constituent element of physical reality in the metaphysics of Leibnitz.
 Biology. A single-celled microorganism, especially a flagellate protozoan of
the genus Monas.
 Chemistry. An atom or a radical with valence 1.
 [Latin monas, monad-, unit, from Greek, from monos, single.]
 
 Aren't elements in lisp called atoms?
 
 According to another online source, Epicurus called the indivisible bits that
made up the world "monads" while Democritus famously called them "atoms". (In
ancient Greek, of course. English wasn't invented for at least twenty years
after Epicurus.)
 
 So "monad" is just another word for "atom", a synonym used for the specifiic
meaning above, I guess.
 
 Paul


Sweet!  Now *that* is making some sense.

Ok, so a monad contains impure state, but it is something indivisible & 
impenetrable so that you cannot access that impure state.

Thanks Paul.

--bb