Why would anyone want opacity?

[Gerald Jay Sussman <gjs@martigny.ai.mit.edu>]

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     Subject: Re: Why would anyone want opacity?
     In-Reply-To: Your message of "Thu, 9 May 96 14:02:20 -0400"
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     Date: Thu, 09 May 1996 14:51:15 -0400
     From: Matthias Blume <blume@CS.Princeton.EDU>

     From: "Guillermo J. Rozas" <gjr@martigny.ai.mit.edu>
     Subject: Re: Why would anyone want opacity?
     Date: Thu, 9 May 96 14:02:20 -0400

     > I guess the real difference is that I do not view at all our job as
     > making the _task of programming/coding effectively_ easier, but
     > instead as making the _task of thinking about processes and
     > algorithms_ easier.  This is a clear corollary of really believeing
     > that the primary purpose of a programming language is to communicate
     > between humans precise process development information, and only
     > incidentally to make computers carry out some actions.
     > 
     > Strong checking of types and abstractions may (I don't believe
     > it but I won't be as adamant) help train effective coders and keep
     > them "on the good path".  I am quite certain that it just gets in the
     > way of _thinking_ about processes and algorithms.

     And I am quite certain (and this is from own experience -- I am a
     convert on this issue!), that strong typing and abstraction *help*
     thinking about processes and algorithms.  I have been arguing this for
     a while now, and others have supported my view.  Maybe it doesn't work
     for everybody.  But at least in my case I know that I simply *refused*
     to accept it for a long time, and only when the evidence became
     overwhelming I finally admitted it to be a truth. (subjectively, of
     course)

     -Matthias

I don't see how ENFORCEMENT of a restriction, such as strong typing,
has anything to do with thinking.  ENFORCEMENT is a management tool.
I have no objection to optional mechanisms that advise or warn you
that you are violating some restriction that you want to impose on
yourself to aid your thinking, but I strongly object to you REQUIRING
me to abide by your intellectual crutches.  I would not impose my
crutches on you!