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Comment by dkarl | Hacker News Reader

Easily understood? Looking at that link, the term has been used by many different philosophers with many different meanings. Leibniz's monads are the most famous, and they have nothing in common with category theory monads except the name.[0]

The mathematical concept was in use for years before anybody decided to call it a "monad" anyway. According to Wikipedia: "The notion of monad was invented by Roger Godement in 1958 under the name 'standard construction'. Monad has been called 'dual standard construction', 'triple', 'monoid' and 'triad'. The term 'monad' is used at latest 1967, by Jean Bénabou."[1]

[0] https://en.wikipedia.org/wiki/Monadology#Summary

[1] https://en.wikipedia.org/wiki/Monad_(category_theory)#Termin...

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So what? If you call it god around 0 BC and monad in the 1970 it's still the same concept. If the notation and meanings change in your pov and that gives you headaches, that's maybe related to the fact, that you cannot call an absurd function, but you can derive structure from combining it.

In other words, God is just a monoid in the category of endofunctors‽

Is this taken word by word from wikipedia?

A monad is an entity that has no purpose other than relation to itself, but can be part of a structure that employs functionality or meaning. I think the problems around this concept for most is, that causality is not a requirement yet, so things don't have to make sense to be part of constructing upon them.

An analogy in IT might be, that worrying about traversal of a graph is a problem domain in time and space and causality that involves questions around loop detection and recursion because you deal from a pov that has those constraints. But that's not a problem yet in the domain of structure as it.

This took some brain, so i hope it's a good try on explanation.

>> In other words, God is just a monoid in the category of endofunctors‽

> Is this taken word by word from wikipedia?

You're either very naive or explaining yourself very poorly.

Both likely - care to explain further?

> Leibniz's monads [...]have nothing in common with category theory monads except the name.[0]

The monad is something about which you can reason but you cannot look inside because it is windowless. No quibbling, please.

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