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Comment by platz | Hacker News Reader

As Brian Beckman explained, as an aside, in "Don't fear the Monad" [1], these two differing views were born in the '70s and split two programmers into two camps:

The bottom-up people, and the top-down people:

- The bottom-up people start with the hardware and only add abstractions and trade performance where necessary (fortran, c, java)

- The top-down people started with perfect abstraction/logic and reduced/removed abstraction to get access to the hardware and performance where necessary (lisp, ml, haskell)

I don't think the two camps may ever get along. Kind of like our version of Conservative and Liberal. (nor should they, in the true spirit of democracy?)

[1] http://www.youtube.com/watch?v=ZhuHCtR3xq8

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> The bottom-up people [...] only add abstractions [later]

I don't think bottom-up verses top-down are like political camps. I think it's more innate, like right-brained vs. left-brained.

I can't understand abstractions till I first understand the lower level. I could never learn algebra without first learning arithmetic. (BTW, I'm old enough to have lived through the New Math philosophy which insisted that every grade school text book start with a chapter on set theory before moving on to, say, fractions.) This doesn't mean that I can't start with a functional model, but it does mean that I start with simple functions and move up.

I don't think anyone understands abstractions right away. Most people learn through examples, and have to recreate the abstractions themselves, even if the abstraction is explained as well as possible.

I think the main difference is purely in which abtraction people prefer to think in (imperative, OOP, functional, etc) but everyone wants to turn it into something else because to them, their model "feels" more right.

Good points, didn't know about New Math, but the failure is very insightful. I'm not sure if perhaps there should be a distinction between operational abstractions vs logical abstractions.

Scripting seems sit in a strange middle ground. Scripting languages tend to be very high level, but are often very approachable for beginners, e.g. Logo

As someone who's strongly in the "top down" camp by observation, I'm about to refute an interpretation of what that means.

Everyone who's learned Haskell really well understands exactly that you learn monads by example, not abstraction. Abstractions need both motivation and "point samples" which describe good reasons for their particular brand of abstract behavior to be meaningful. I don't think at all that the "top down" side actually must work top down, but instead simply values the tools you get when you reach the top, i.e. strong reasoning capabilities and metaphor connections to algebra.

I really want to change the Crockford Monad Curse to instead read that "Anyone who's just learned monads is suddenly incapable of explaining them". When they first "click" you become obsessed with the abstraction as a thing instead of using it as a tool to better leverage patterns which turn up in real examples. Until you shake that by just using monads so frequently that you're damn bored you cannot properly explain them.

Same thing happens with design patterns. It probably happens with all sorts of non-obvious but powerful ideas. Hmm. Any sufficiently advanced learning is indistinguishable from madness?

That's what Plato suggested in his Allegory of the Cave, at least. :-)

I don't agree. There's many a programmer I know that can troubleshoot a tube radio, then go write some Lisp. Most are old school folks that grew up in the 8 bit days of solder and wirewrap.

Individuals do both, yes, but disagreeing that there are in fact camps is something else.

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