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Re: Pizza Example

From: Anthony W. Youngman <>
Date: Wed, 7 Apr 2004 01:08:42 +0100
Message-ID: <>

In message <yRzcc.51347$>, Eric Kaun <> writes
>"Anthony W. Youngman" <> wrote in message
>> Somebody gave me a wonderful quote recently. "Logic and mathematics give
>> you a consistent model. Academicians have an unfortunate tendency to
>> confuse consistency with truth."
>It's an interesting quote, but I'm not so confused. Fine - consistency isn't
>truth, and let's assume that it doesn't even imply truth. How would you
>judge the "truth" of a model? Such doesn't even make sense, really. Models
>are useful or not. Consistency is one of the best measures we have, but that
>doesn't mean it's perfect. Out of curiosity, how do you judge a model?

How do I judge a model? Simple, really. How good a match to reality is it? As a scientist, can I use it to predict the future?
>This argument is tired: "Someone has a model. Models aren't truth.
>Therefore, I can use any model I like." Which is true in a degenerate sense,
>but also useless.

Newtonian Mechanics is a perfectly consistent mathematical theory. Yet if I try to predict where Mercury will be in a year's time, using Newtonian Mechanics, I am going to get it embarrassingly wrong.

What is important is knowing which models are appropriate, and when - I would perfectly happily use Newtonian Mechanics to calculate the orbit of Venus ... it's just that I know the answer will not be perfect. And while the error is insignificant for Venus, it's very noticeable for Mercury.
>> As for you being worried if you could understand engineers or doctors -
>> I'm sorry, but I don't see why I should assume that other people are
>> better than me.
>Hmmm. In other words, you assume that you, your significant other, or your
>garbageman are equally adept at performing a quintuple bypass, or perhaps
>walking a tightrope 20 stories up on a windy day or cleaning a nuclear

Actually, while I couldn't do any of those three, I do happen to understand the theory behind them. And certainly with regard to "cleaning a nuclear reactor", I would expect I understand it a damn sight better than the person doing it - he's probably an underpaid "monkey" (no disrespect meant - but they pay peanuts, what do they expect?) following a procedure by rote.
>You should assume people are better than you because they are; not on a
>single all-encompassing nonsensical "person-goodness" axis, but rather on
>axes of specific abilities.
>> If I can't understand (at least superficially)
>And that's the key: there are nuances in every field that are very difficult
>to acquire without years of experience.

As regards practical ability, I would agree with you - I don't practice my trombone enough :-) But as regards *UNDERSTANDING*, I would disagree. Most people either have the intelligence to do so and quickly, or they struggle and never get there. And unfortunately, an awful lot of practitioners of every discipline seem to fall in the latter category. They know how to deal with what they meet every day because they have the experience, but if something subtly changes then they're all at sea because they lack understanding. There's a massive gulf between the guy who's practised his craft, and the guy who understands his craft.
>> what
>> they're doing, then I conclude they are either crap at explaining
>> themselves or, worse, they don't understand themselves.
>Frequently the former, sometimes the latter, but sometimes simply a lack of
>verbal ability that wouldn't necessarily lead me to assume they don't
>understand what they're doing. I think you need some additional measures.
>Anti-intellectualism is a poor foil for intellectual elitism.

I respect people for their abilities. But - I'm a scientist - I understand Physics - and I get well pissed off when (for example) I predict that my plumber's proposed solution to a problem will fail. So he goes and does it, and it fails! He'd put the boiler next to the tank, so the water wasn't circulating. So he raised the output pipe (something to do with increasing the distance the water could rise or fall). Of course it didn't work! We had to put a pump in, which he'd said would be unnecessary.
>> And I'm sorry if
>> I'm cynical, but I've had enough experience of various professions (and
>> from my own research) to know that people are very good seeing what they
>> want, and not seeing what they don't want. I don't trust "experts". Far
>> too many of them wear blinkers :-(
>Of course you trust experts; you use products every day that were theorized,
>designed, and built by them. If you really didn't trust experts you
>certainly wouldn't be using this Infernal Machine. Yes, people see what they
>want - are you that different? I'd say blinker-wearing is just as true of
>those who do what's most obvious and immediate; the straightforward answer
>isn't always the right one.

DO I trust the experts who designed this infernal machine? I have a pretty decent grasp of the theory. So I don't need to. I can (should I wish to) check it out for myself. And if something "feels wrong" I nearly always do.

I might not be able to fix my car. But I have a damn good idea of what needs to be done. And if the mechanic can't explain WHAT he's doing, and WHY, I don't trust him anywhere near my car!
>- erk


Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
HEX wondered how much he should tell the Wizards. He felt it would not be a
good idea to burden them with too much input. Hex always thought of his reports
as Lies-to-People.
The Science of Discworld : (c) Terry Pratchett 1999
Received on Tue Apr 06 2004 - 19:08:42 CDT

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