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Re: Re: Re: Re: error with Sum and

• To: mathgroup at smc.vnet.net
• Subject: [mg102486] Re: [mg102459] Re: [mg102443] Re: [mg102437] Re: error with Sum and
• From: DrMajorBob <btreat1 at austin.rr.com>
• Date: Tue, 11 Aug 2009 04:03:23 -0400 (EDT)
• References: <h5bk64$hlm$1@smc.vnet.net> <200908070932.FAA15211@smc.vnet.net>
• Reply-to: drmajorbob at bigfoot.com

I'd never assume my wrench or screwdriver is perfect; but I do expect them  
to behave in similar fashion every time I pick them up.

Bobby

On Mon, 10 Aug 2009 03:14:12 -0500, Elton Kurt TeKolste  
<tekolste at fastmail.us> wrote:

> There is a concept in the computer programming community called the
> "leaky abstraction." (See http://en.wikipedia.org/wiki/Leaky_abstraction
> )
>
> The gist of this concept is that (to a first approximation) all
> human-implemented abstractions leak -- no matter how hard you try, there
> will always be in some circumstances manifestations of the lower-level
> infrastructure that supports the abstraction.
>
> So, for example: TCPIP always delivers correct packets -- unless the
> transmission lines are down or your power supply is interrupted.
>
> In this case, the abstraction that leaks is the ability to make a proper
> symbolic sum.
>
> The reasons that all abstractions are leaky are
>    1)  it is generally not humanly possible to anticipate all of the
>    situations in which the nasty plumbing will become visible
>    2)  to the extent that it is humanly possible it is not generally
>    practical to fix them all (you probably don't want to know what
>    Mathematica would cost if it were perfect, or how long you would have
>    to wait to see it)
>
> In the real world, where cost and time matters, each of us needs to take
> ultimate responsibility for the correctness of our results and not
> presume that our tools are perfect.
>
> Kurt
>
>
> On Sun, 09 Aug 2009 18:19 -0400, "Richard Fateman"
> <fateman at cs.berkeley.edu> wrote:
>> George Woodrow III wrote:...
>> > Also including a private response from Richard:
>> >
> Regards,
> Kurt Tekolste
>
>



-- 
DrMajorBob at bigfoot.com

• References:
  • Re: error with Sum and Infinity
    • From: Richard Fateman <fateman@cs.berkeley.edu>