[Edu-sig] [BULK] More OOP bashing (& which metaphor is best?)

Peter Chase pchase at sulross.edu
Wed Apr 4 17:14:49 CEST 2007

Paul D. Fernhout wrote:
> I just came across these links (bearing indirectly on the value of
> Python emphasizing both procedural and Object-Oriented Programming
> support as a language good for beginners and experts):
> See:
>   "Object Oriented Programming Oversold!"
>   http://oop.ismad.com/
> Or:
>   "Guide To Myths"
>   http://www.geocities.com/tablizer/myths.htm
> And:
>   "Why I Prefer Procedural/Relational Over OOP"
>   http://www.geocities.com/tablizer/whypr.htm
> >From the last, for example: "It is my opinion that the division between
> data and behavior in procedural/relational (p/r) applications also has
> software design benefits. It allows a certain "contract" between the
> database and the database user (application programmer). Contracts
> usually have certain obligations and costs, but these costs are
> worthwhile for the parties of the contract or else the contract would
> not be entered into. The relational paradigm involves just such a
> contract. If you follow your end of the bargain, then the other party,
> the relational paradigm, will provide wonderful benefits. The
> "limitations" required are not arbitrary, for they provide a powerful
> intellectual rigor which is one of the greatest tools of modern software
> technology in my opinion. Along with GUI's, relational technology is one
> of the rare "wow!" technologies that is a fundamental leap forward in
> software design. ... The contract of the relational paradigm basically
> says, "If you put or keep your information (data) in a certain given
> structure, then there are powerful and concise operations that you can
> do on this information."  E. Codd, the inventor of relational algebra,
> opened the world's eyes to a powerful kind of "math" (with some help
> from more practical-minded collegues). This math can reduce complex
> structures and patterns into relatively simple formulas, or "relational
> math"."
> Of course, one might argue relational databases are just well defined
> objects... :-) But then the object paradigm starts to break dawn -- and
> one is really thinking more in terms of "modules" then how "objects" are
> usually discussed. As I previously wrote here (and on the Squeak list a
> long while back):
>   http://mail.python.org/pipermail/edu-sig/2006-December/007483.html
> "Personally, one way my opinions differer from Alan Kay's in a deep way
> is on his, I think mistaken, notion that an object (or a class) can have
> any  meaning apart from the ecology of objects (or really classes) it is
>  embedded in. I think there is a deep philosophical (and practical)
> point  there which he is perhaps only slowly beginning to see. :-) But
> it is reflected in the superiority of, say, Python's modularity in
> practice  compared to early Smalltalks, that is, if you think classes
> stand alone, then there is no need for a higher level of "module",
> whereas if you think  classes need to be clustered to support each
> other, than modules make a lot of sense."
> Still, I think the more general issue, present even in AK's new
> proposal, is how one can simulate the world by objects but one also can
> simulate the world (perhaps more accurately, if with more effort) as a
> set of fields defined by relations (or by any other method). Whether
> such fields are best implemented procedurally or via OOP is another
> question. Anyway, when one delves this, it gets murkier and murkier --
> in part because people often confuse having a modeling layer of discrete
> objects somewhere as meaning the models are all about Objects and OOP,
> but there is no reason one cannot use objects to model other things
> (fields) -- or even vice versa. Still, from a beginner point of view,
> why should you have to get the metaphor of "objects" if what you are
> interested in are "fields" (e.g an astrophysics simulation of particles
> in an electrostatic gradient and/or gravity well)? I think the appeal of
> APL based on arrays is in part the appeal of fields.
> One thing that makes this all confusing to understand is the human mind
> has a layer (or module) that models the complex real world in terms of a
> simplified representation of "objects" (as I wrote in my undergraduate
> thesis in 1985: "Why Intelligence: Objects Stability Evolution and
> Model"). William Kent explored this in his book _Data and Reality_:
>   http://www.bkent.net/
> For example, by numbers, people are about 90% bacteria, but we generally
> don't see other people as walking bacterial colonies. :-)
>   "People Are Human-Bacteria Hybrid"
>   http://www.wired.com/medtech/health/news/2004/10/65252
> Yet if you want to understand some branches of holistic medicine (and
> why using antibiotics might have lifelong health impacts) then you need
> to think about people this way, as hard as it is.
>   http://www.findarticles.com/p/articles/mi_m0NAH/is_2_32/ai_83316363
> And then, if you want to understand bacteria, you have to see them more
> as a vast worldwide supercomputer than isolated individuals:
>   "New Science Of Metagenomics to Transform Modern Microbiology?"
>   http://science.slashdot.org/article.pl?sid=07/04/02/2017249
> So, as Plato's "Allegory of the Cave" suggest it is sometimes hard to
> see past these shadows (objects) to realize that reality is something
> fundamentally different (deeper, more complex, more interrelated) than
> the simple parsing into objects we do routinely. [Plato's analogy breaks
> down here though in that he still thought of *ideal* forms of objects,
> whereas I'm more arguing against even ideal forms, except perhaps in a
> statistical sense sometimes.) Seeing the world in terms of objects may
> have enormous survival value to life forms with big brains, but that
> does not mean it is completely accurate (even as objects being a useful
> idea does mean there is likely some statistical truth there (e.g.
> statistical clustering), in terms of a field of relationships).
> Still, and I don't have it anymore, but about fifteen years ago I made a
> list of about 20 reasons why (VisualWorks) Smalltalk was better than a
> typical C++ (of the time) from a developer and maintainer point of view
> -- intentionally not bringing in OOP specifically as a reason (although,
> in retrospect, many of the benefits were enabled by OOP). Stuff like the
> integrated debugger, the browser, the inspector, refactoring support,
> garbage collection, the GUI library, edit/continue, and so on. Of
> course, C++ now apes many of those features, but without the integration
> or elegance.
> Still, having explored relational programming (via Pointrel) I can say
> both approaches (OOP and Relational) have their merits. The right tool
> for the right job. Or in this case, a flexibility with metaphor, so "teh
> right metaphor for the right job". Or, looking at it even more
> abstractly, "the right mathematical abstraction for the right job". And
> from that point of view, should not a goal of computer education (and
> CP4E) be to have people able to handle multiple metaphors as appropriate
> for the situation? Programming a digital thermostat might require
> thinking in terms of one kind of metaphor, whereas programming the GUI
> on your car smith require a different kind of metaphor?  Perhaps the
> conflicts about "which programming language is best" really are just
> obscuring the issue of "which metaphor is best" and the answer to that,
> like when looking at a large library of fiction, is that lots of
> metaphors are useful in the right situations, and only being able to
> understand one kind of metaphor would mean you would not get very much
> out of most fiction. So a programmer only capable of working within one
> metaphor is not a very capable programmer. Still, if that metaphor is
> very powerful, like with OOP, a single-metaphor programmer could still
> get pretty far and do lots of useful things. And likely further than
> simple relational programs.
> Anyway, food for thought.
> --Paul Fernhout
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Not sure you can trust anyone using the phrase "appeal of APL".

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