Jonah Thomas wrote:
> John Doty
whispertel.LoseTheH.net> wrote:
> >> Should 18th century physicists have abandoned Newtonian mechanics and
>> returned to a belief in Aristotelian physics when Berkeley showed that
>>
>> it was based on fallacious reasoning? Straight answer, no evasion
>> please.
>
> There were more than two choices available.
>
> Your language reflects your ideas. When the language contains logical
> contraditions, it's sloppy.
Yes, but that can simply reflect the difficulty with language. Einstein
insisted that his ideas were visual, not linguistic. Language has its
limits.
> Usually what has happened is that you've
> given the same names to two different things,
Are there different things? Language insists on dividing continua.
> and you use them as if
> they were the same thing. That's a clue to how to refine your language.
It's an infinitely long road.
> Give the different things different names and the contradictions go
> away. The language gets easier to use, because you don't have to "just
> know" which times the names refer to one thing and which times to
> another.
It requires an infinite vocabulary, but we are finite creatures.
>
> This is what traditional logic is good for. It provides the evidence
> that there are problems that need to be cleared up, and it provides
> clear hints about just what the problems involve. Sometimes the problems
> can't be fixed because the thinking was wrong.
>
> What should have been done about Newton was what was eventually actually
> done. They fixed up the problems and showed where Newton's ideas worked
> and where they didn't.
Who are "they"? In physics, we still use use the 18th century approach
to calculus. Sure, we let the math department expose the freshmen to δ-ε
proofs and all that, but that's really just to immunize them. It also
keeps the mathematicians from getting too upset with us. But then we go
ahead and teach physics without that baggage. Few professional
physicists remember how the δ-ε method works: it's not a particularly
useful tool. Calculus works fine without it.
> As it turned out, the circumstances that didn't
> work out tended to be things that never come up in practice so that was
> all OK. But it might not have been. They were correct to check.
The reality check was in the experiments, not the logic. To be sure, the
elucidation of these issues by the 19th century analysts is a
fascinating story of puzzle solving. But it had no significant impact on
physics.
Besides, what was checked? As Berkeley would correctly tell you, logical
argument is based on faith. Given logic's history of failure outside the
world of formal mathematical proof, I hardly see how fixing up the logic
of calculus should have any direct significance for physics. Physics
needs a firmer foundation.
>
> You have done this "Either it's one or the other" in several contexts
> now. You consider the existing conventional wisdom and then you consider
> one new idea, and you talk as if one or the other of them must be right.
> This is unscientific. If you show that the CW is wrong, it does not mean
> that any particular alternative must be right.
Unscientific? *All* scientific inquiry is like this. Science proceeds by
falsification. One can *never* in science prove a hypothesis is true.
> They could easily both be
> wrong.
Happens all the time. But what can you do except look for a better one?
> And if we have two hypotheses that fit the existing facts, we
> don't need to choose between them. At that point it's good to look for
> predictions that they make differently, and then go out and see what
> actually happens. If one set of predictions fails, then that hypothesis
> is wrong -- though there might be an easy way to patch it up to fit. If
> both sets of predictions fail then we have something interesting.
Yep. Now *that's* science!
>
> If you define something named A, then you want the definition to be nice
> and clear. If you get A and ~A at the same time, it means you haven't
> defined A clearly enough after all.
The law of the excluded middle. Classical logic's most powerful and
sloppy postulate. Not always present in modern formal logics, and often
violated by physical models of logic (what happens if you connect the
output of a logic inverter to its input?).
> But it's a choice between A and ~A.
> It isn't a definite choice between A and B.
Bohr would vehemently disagree.
>
> Here's how I've understood your basic argument: If Forth was the best
> computer language it would have taken over the computing world by now.
Gross exaggeration of my position.
> It has not done so. So it must have one or more fatal flaws that keep it
> from being great.
Consider the history. Forth *was* a widely respected and used language
circa 1980. But C ate its lunch. And the explanations that do not
involve flaws in Forth (including its culture) don't work.
> The obvious conclusion from that is that we should
> form a harmonious group that searches through everything we know about
> Forth and other languages to identify Forths Fatal Flaws (appreviated
> 3F). Once we get a consensus what the 3Fs are then we can harmoniously
> cooperate to fix them. This will give us a new language that we can
> label "Forth" which will inevitably take over the world.
Nah. We should be *experimenting*. We should be publishing stuff people
will use (not yet another Sudoku solver). "Underground Forths are needed."
>
> Various people have proposed other things that have kept Forth from
> taking over the world. You have rejected each of them on dubious
> grounds. For example, there was the argument that Forth has never gotten
> enough institutional support. You said that this couldn't have been The
> Reason because languages that got the *most* institutional support
> (PL/1, Ada, etc) have tended to fail and be replaced by other languages
> that got less institutional support like C and Java. But consider --
> would you be certain that Forth has only one Fatal Flaw, and that only
> Forth has one? Perhaps the languages that got the most institutional
> support happened to have fatal flaws of their own that kept them from
> great success despite that support.
Sure. You ever program in PL/I? Ugh! But then, there are also many
examples of languages with weak early institutional support like C and
Python that have done very well.
> While C and Java got *enough*
> support that the lack of it didn't stop them.
C? AT&T's support for C came *after* its success was clear. Before that,
it was just a toy to keep their CS research group happy and productive.
> And Forth got none.
Forth had lots of institutional support in astronomy: why didn't it
continue to thrive there?
The history you're trying to sell here is not what I experienced.
Indeed, if Forth had not been a significant player in astronomy, I'm
sure I never would have used it.
> I
> remember when Forthers were tremendously excited because Harris
> Semiconductor was making the RTX chips. It wasn't just that there were
> going to be 16-bit specialty Forth chips. It was that Harris was
> providing Forth with its first ever institutional support. And then
> Harris mothballed the RTX. Forth has survived with no overt
> institutional support whatsoever, except for what Harris provided.
> Whatever institutional support Forth has gotten has come from classified
> military programs and secret business ventures.
Pure nonsense. Was it just hobbyists using Forth at MIT, SAO, NRAO,
KPNO, etc.?
> Arguing that such
> support is not necessary is like arguing that water is not necessary for
> human survival because some people with plenty of water have died of
> exposure while others with less water survived.
That's not my argument. Forth got plenty of early support, similar to
what C got but earlier.
>
> More important, you have championed the idea that computer languages
> should fit in with the ways that people are predisposed to think. But
> you violated that idea by your presentation. What you're saying would be
> fine if you collected a bunch of guys who used to use Forth and who were
> kind of nostalgic for it, who had to quit using it because it didn't
> work for them. They'd be predisposed to believe in 3F. They might get
> all fired up to remove the 3Fs and create the language that will take
> over the world the way Forth should have. But apart from logic or truth,
> remember the old DC saying, "Where you stand depends on where you sit."
> Several of us are Forth vendors. It would be silly for them to believe
> in 3F. Many of us think of ourselves as Forth programmers. Why would we
> want to believe in 3F? You seem to believe that agreeing about 3F is the
> only way we could ever go on to the second step.
But those who've given up think even less of its future. It's rocky
here, but it's bare lava there.
>
> But what if you instead presented interesting ideas. Could we build an
> extension onto Forth that wasn't postfix? Of course we could. We mostly
> haven't bothered because we haven't much wanted to. If we had such a
> thing we could measure how much extra complexity it added to a Forth
> compiler. We wouldn't have to argue about whether it would be too
> complex, we could measure it. We could measure the slowdown in runtime
> and the slowdown in compile-time. There might be people who'd find those
> penalties acceptable. After all, there are people who use scripting
> languages that are 10 times slower, or even 50 times slower, and they
> don't complain. If infix or whatever only doubled execution times we'd
> be getting off cheap. And nobody has to use them. If you got some
> customers who were interested in that sort of thing then you might get
> Forth vendors competing to see who can best provide it. They don't have
> to say they believe in 3F first. They want to create things that give
> them income and bragging rights. Give them the idea that customers would
> value a particular change (that they can add on top of their Forths) and
> they'll be happy to look at ways to do it. You don't have to persuade us
> about 3F first.
You're going down the MAGIC/L road. It almost worked for Loki. What was
missing there? Can it be fixed? What can we learn from their failure and
other successes? I think Python is telling us a lot about libraries.
>
> We don't have to agree about what's worth doing. As Bruce McFarling has
> said, the more different things we try the more likely one of them
> works.
"Underground Forths are needed".
> It's got to be easier to persuade Forthers to look at interesting
> things that could be done with Forth than it is to persuade them that
> some of the things that have not yet been done with Forth are Fatal
> Flaws because they haven't been done yet.
>
> Please! Give up the worthless side issue of Fatal Flaws and tell us
> about things we can try out.
"Underground Forths are needed". I'm very pleased by the recent
StrongForth discussion, as it seems to me that the StrongForth approach
fixes some major issues that prevent traditional Forth from being used
as a reasonable foundation for a user-friendly language.
--
John Doty, Noqsi Aerospace, Ltd.
http://www.noqsi.com/
--
History teaches that logical consistency is neither sufficient nor
necessary to establish practical, real world truth. Those who attempt to
use logic for that purpose are abusing it.
