[sci.philosophy.tech] Layman's argument for Occam's razor

dmb@morgoth.UUCP (David M. Brown) (08/23/87)

The purpose of a theory is to simplify.  Seemingly disparate phenomena
are unified, or integrated, into one.  The purpose of this is similar
to the need for modularity in programming - to hide details.  If I am
basing a theory upon some other theories, I want to use the ones which
have less assumptions to check, preferably none!  Therefore, Occam has
given me good advice.

But what, someone asks, if the simpler theory is not the "right" one?
Perhaps you philosophers avoid this question.  If so, then you need
not consider Occam's Razor as anything more than advice.  If not, then
we are entering the realm of "Truth" (absolute, relative, whatever). 

One argument given recently was that simplicity has an aesthetic
component, which touches our innate ability to directly sense Truth.
I agree with this, but others were not convinced that this sense is
accurate.

Because we are talking about matters of the mind, it might be
appropriate to discuss the origin of the mind.  Basically, minds have
evolved because they have survival value.  The ability to generalize,
to hide detail, and therefore to deduce, to look ahead, to imagine, has
given us the ability to survive.  I submit that if we had generalized,
etc., in the wrong directions, we would have died (probably many did).
Our process of generalization (ie, simplification) gave us survival
value only because it was in the right direction.  For example, it was
absolutely correct to consider the leaves, branches, trunk and root as
one entity, the tree.  That was the *correct* simplification.

As our thought processes encompassed more and more phenomena, and as
we questioned things we previously took for granted, formal theories
evolved, along with formal method(ologie)s.  However, let's remember
that these formalisms are based upon assumptions so innate that they
are practically hard-wired.  

When a theory becomes too complex (at any one particular level), when
it has loose ends, when it has jagged edges, when it is not simple,
our aesthetical sense, derived from millions of years of being right,
tells us it's wrong.  
 
Did you have a picture in your mind of 'loose ends', etc.?  What is
that a loose end of?  What are those lines?  I can't answer that
exactly, but I think they are really *there*.  Where?  Somewhere you
can only see/be with your mind.  Somewhere where conception differs
but little from perception.

Another discussion in this newsgroup concerned Taoists.  I think their
symbol, the Yin-Yang, is relevant here.  Among other things, the
Yin-Yang is a symbol of the process of simplification, or
generalization, of abstraction.  The black and white represent
specific details, the circle into which they combine represents the
general.  As such, it can be mapped into an upside-down letter Y:

                               |              <-  simple
                               |
                              / \
                             /   \            <-  complex 

This is the basic structure of the hierarchy of dependencies and
conclusions which comprise any theory.  Multi-branched nodes can be
represented as sets of binary branches.

The universe, of course, isn't as simple as this.  It's not a simple
hierarchy, except locally.  Note that the duality represented by the
binary branching can ba mapped onto the duality between duality and
oneness.  The tree becomes a graph.  Self-reference is encoded at the
highest level.  Does this have something to do with Godel?

Anyway, I have strayed from my original intentions.  Trust your mind.
It got you this far.

David Brown
{harvard | ll-xn | mirror}!adelie!morgoth!dmb
GZA, 320 Needham St., Newton Upper Falls, MA  02164
(617) 969-0050

 WE CHALLENGE our traditions
      BECAUSE we believe
        TRUTH without questioning
     IS FALSE





  

kube@cogsci.berkeley.edu (Paul Kube) (08/24/87)

In article <433@morgoth.UUCP> dmb@morgoth.UUCP (David M. Brown) writes:
>One argument given recently was that simplicity has an aesthetic
>component, which touches our innate ability to directly sense Truth.
>I agree with this, but others were not convinced that this sense is
>accurate.

Are you counting me among the `others'?  I don't doubt that our
intuitions about what's true are sometimes right, and even reliable
over some domains.  I do doubt, though, that these intuitions are
reliable when applied to anything as complicated as a serious
scientific theory; do you really mean to suggest that you can tell if
a serious empirical theory is true just by thinking about it?

>I submit that if we had generalized,
>etc., in the wrong directions, we would have died (probably many did).
>Our process of generalization (ie, simplification) gave us survival
>value only because it was in the right direction.  

That we have survived as a species shows at most that we have not got
it so wrong as to have been put to serious disadvantage with respect to
our ecological competitors; it does not show that we have got it right. 
So far as physics goes, our innate endowment seems to have left us
stranded somewhere pre-Aristotle:  good enough given our niche
and maybe more useful than the correct theory given the computational
limitations of our wetware, but wrong nevertheless.

I would think that the kinds of cognitive capacities that tend to
enhance reproductive success are primarily things like being able to
tell if a mating candidate is fertile or whether the thing you're
looking at is edible.  Our intuitions are bad enough here; what reason
is there now to think that we have evolutionarily honed intuitions
for detecting correct mathematics, or quantum mechanics, or astrophysics?

--Paul kube@berkeley.edu, ...!ucbvax!kube

myers@tybalt.caltech.edu (Bob Myers) (08/24/87)

In article <433@morgoth.UUCP> dmb@morgoth.UUCP (David M. Brown) writes:
>The purpose of a theory is to simplify.  Seemingly disparate phenomena
>are unified, or integrated, into one.  The purpose of this is similar
>to the need for modularity in programming - to hide details.

Yes. But why do you hide the details? So it's easier to think about,
I would say.

>But what, someone asks, if the simpler theory is not the "right" one?
>Perhaps you philosophers avoid this question.  If so, then you need
>not consider Occam's Razor as anything more than advice.  If not, then
>we are entering the realm of "Truth" (absolute, relative, whatever).

I really don't think that science deals with "Truth" or "right"ness.
It does deal with accuracy and explanatory power. Explanatory power
has two halves: simplicity, so we can understand it, and generality,
so it covers more than a narrow range of phenomena.

>One argument given recently was that simplicity has an aesthetic
>component, which touches our innate ability to directly sense Truth.
>I agree with this, but others were not convinced that this sense is
>accurate.

I'm not sure what Truth you're talking about here. Do you mean
scientific truth, as in the likelyhood of some scientific theory being
accurate to such and such a degree, or are we back to some sort of
innate philosophical truth? I don't think we can sense directly
the accuracy of a scientific theory.

>Because we are talking about matters of the mind, it might be
>appropriate to discuss the origin of the mind.  Basically, minds have
>evolved because they have survival value.  The ability to generalize,
>to hide detail, and therefore to deduce, to look ahead, to imagine, has
>given us the ability to survive.  I submit that if we had generalized,
>etc., in the wrong directions, we would have died (probably many did).
>Our process of generalization (ie, simplification) gave us survival
>value only because it was in the right direction.  For example, it was
>absolutely correct to consider the leaves, branches, trunk and root as
>one entity, the tree.  That was the *correct* simplification.

Nonsense. That was the *useful* simplification. *Useful* in that it
increased survivability. There is nothing to make any simplification
any more "correct" than any other, other than degree of accuracy.
And the usefulness of such simplifications varies *greatly*, depending
on your purposes.

>When a theory becomes too complex (at any one particular level), when
>it has loose ends, when it has jagged edges, when it is not simple,
>our aesthetical sense, derived from millions of years of being right,
>tells us it's wrong.

Hmm. For whatever it's worth, I don't think this is right. I think
there is a failure to comprehend a theory that gets too complex --
comprehend on an intuitive level -- which is of course yet another
simplification. I feel that the isomorphism between my mind and
physical reality is not very good. I don't think we're told it's
wrong, but that we don't understand it well.

A theory is only "wrong" insofar as it is inaccurate. But it is only
useful insofar as it is accurate AND understood.

>Did you have a picture in your mind of 'loose ends', etc.?  What is
>that a loose end of?  What are those lines?  I can't answer that
>exactly, but I think they are really *there*.  Where?  Somewhere you
>can only see/be with your mind.  Somewhere where conception differs
>but little from perception.

I think this is more of a psychological problem. Some people (including
me) think in pictures. Images come to mind when I think about things.
I think it's just another way of representing within your mind what
goes on around you. Another way of making the isomorphism between
reality and your mind. Many people have a good understanding of what
they can picture.

It's just a simple step beyond that to represent concepts within your
mind as pictures, too. If the brain is hard-wired for anything, it`s
hard-wired for dealing with perception. Hundreds of millions of years
in the making. Why not make use of that hardware?

-------------------------------------------------------------------------------

Bob Myers                                         myers@tybalt.caltech.edu
			 {rutgers,amdahl}!cit-vax!tybalt.caltech.edu!myers

sarge@thirdi.UUCP (Sarge Gerbode) (08/25/87)

In article <20264@ucbvax.BERKELEY.EDU> kube@cogsci.berkeley.edu.UUCP (Paul Kube) writes:
>
>what reason
>is there now to think that we have evolutionarily honed intuitions
>for detecting correct mathematics, or quantum mechanics, or astrophysics?

Only that it seems to be a psychological fact that we have a kind of "built-in
computer" that operates unconsciously (or maybe we get messages from God, or
whatever).  From this source (or Source) we get hunches and "feelings" about
things.  These hunches and feelings often form the basis for scientific
hypotheses that later turn out to be true.

I don't go along with the radical form of "If it feels good, do it!" that was
mandated in the '60s counter-culture, but I think, as Aristotle did, that
pleasure is a sign of the good (and the true).  Therefore, all else being
equal (and it usually isn't), one should (and does) pick the choice that gives
one pleasure, or, alternatively, that appeals to one aesthetically.
-- 
"Absolute knowledge means never having to change your mind."

Sarge Gerbode
Institute for Research in Metapsychology
950 Guinda St.
Palo Alto, CA 94301
UUCP:  pyramid!thirdi!sarge

smoliar@vaxa.isi.edu (Stephen Smoliar) (08/25/87)

In article <3733@cit-vax.Caltech.Edu> myers@tybalt.caltech.edu.UUCP (Bob Myers) writes:
>
>I really don't think that science deals with "Truth" or "right"ness.
>It does deal with accuracy and explanatory power. Explanatory power
>has two halves: simplicity, so we can understand it, and generality,
>so it covers more than a narrow range of phenomena.
>
I think it may be useful to recall Marvin Minsky's definition of the term
"model:"

	To an observer B, an object A* is a model of an object A
	to the extent that B can use A* to answer questions that
	interest him about A.

Thus, we may say that science is concerned with the development of models
which answer questions about different bodies of phenomena, and such models
are generally called theories.  However, the important part of Minsky's
definition which is often overlooked is that part about "questions that
interest him."  Not only is it necessary to scope out the particular body
of phenomena which are under study (A);  but also one must scope out the
nature of the questions one wishes to pose about those phenomena.  Indeed,
one way of looking at Kuhn's paradigm shift is that it entails a major change
in the nature of the questions being posed.

flash@inference.ee.qmc.ac.uk (Flash Sheridan) (09/24/87)

In article <20264@ucbvax.BERKELEY.EDU> kube@cogsci.berkeley.edu.UUCP (Paul Kube) writes:
>In article <433@morgoth.UUCP> dmb@morgoth.UUCP (David M. Brown) writes:
> do you really mean to suggest that you can tell if
>a serious empirical theory is true just by thinking about it?
>
According to Einstein, yes.  He claimed he developed Special
Relativity for its harmony with Maxwell's equations, _before_
Michelson-Morley.

cik@l.cc.purdue.edu (Herman Rubin) (10/04/87)

In article <294@sequent.cs.qmc.ac.uk>, flash@inference.ee.qmc.ac.uk (Flash Sheridan) writes:
> In article <20264@ucbvax.BERKELEY.EDU> kube@cogsci.berkeley.edu.UUCP (Paul Kube) writes:
> >In article <433@morgoth.UUCP> dmb@morgoth.UUCP (David M. Brown) writes:
> > do you really mean to suggest that you can tell if
> >a serious empirical theory is true just by thinking about it?
> >
> According to Einstein, yes.  He claimed he developed Special
> Relativity for its harmony with Maxwell's equations, _before_
> Michelson-Morley.

Certainly William of Ockham, and until recently most philosophers,
believed that it is easy to find "true" theories, and that it is
not difficult to test these theories.  Now it may be that the speed
of light in vacuum is constant, but there is no way to directly test
it.  In fact, according to most of what I read in modern physics, there
is no vacuum!  Thus the real problem is "when should we accept a theory
which we cannot completely test, or which we may even know to be false."
Since there is no vacuum, the Special Relativity transformations, if we
could obtain sufficiently accurate data, would not agree with Einstein's
predictions exactly.

There is no question that the Lorentz-Fitzgerald transformations were
obtained as the set of transformations which preserve Maxwell's equations
before Michelson-Morley, and that Special Relativity follows from these
equations if the speed of light is assumed constant.  However, while the
development does not involve any empirical observations, Maxwell used,
possibly indirectly, empirical results.

On the other hand, I completely disagree that one infers natural laws from
empirical observations!  One only chooses which mental construct to use
among those which the mind can conceive on the basis of observations.
-- 
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907
Phone: (317)494-6054
hrubin@l.cc.purdue.edu (ARPA or UUCP) or hrubin@purccvm.bitnet

franka@mmintl.UUCP (Frank Adams) (10/06/87)

In article <588@l.cc.purdue.edu> cik@l.cc.purdue.edu (Herman Rubin) writes:
>On the other hand, I completely disagree that one infers natural laws from
>empirical observations!  One only chooses which mental construct to use
>among those which the mind can conceive on the basis of observations.

I will certainly agree with that second sentence.  But I think it is also
indisputable that those observations may cause us to conceive mental
constructs which we would not otherwise have conceived.  If that isn't
"inferring natural laws from empirical observations", I don't know what is.

If, on the other hand, you mean to say that we don't *deduce* natural laws
from empirical observations, I will quite agree.
-- 

Frank Adams                           ihnp4!philabs!pwa-b!mmintl!franka
Ashton-Tate          52 Oakland Ave North         E. Hartford, CT 06108