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C00002 00002	haberm[w83,jmc] Jurgen Habermas "Theories of Truth", Wahrheitstheorien
C00009 00003	Book Report
C00021 00004	Additional remarks:
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C00042 00006	Addendum to book report
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haberm[w83,jmc] Jurgen Habermas "Theories of Truth", Wahrheitstheorien

	1. Habermas discusses what the object of true should be, whether a
sentence or an assertion as recommended by Strawson.  My opinion is that
this question doesn't have an optimal solution.  Truth may be applied to
sentences but also to more abstract objects.

	2. Habermas doesn't understand that the usefulness of the
predicate true(p) is in quantified sentences.

	Check whether Habermas says anything that applies to abstract
systems.  Whether Putnam does.  After I write my book report, I should
assign GAVAN a book report. What about dialectics?

	Habermas says:


	There is no doubt a possible theory of speech acts, but it's
losing to connect a reasonably clear notion like truth with all those
complications.

	Another excerpt:


	Well, my notion of truth is certainly different.  In my view it is
possible that some statement on whose falsity everyone who ever lived and
will live would agree is nevertheless true.  It may indeed be possible to
fool all of the people all of the time about some statements.  There is no
god that protects the unanimous opinion of mankind from being mistaken.

	Notice, however, that matters have become increasingly murky.  The
consensus to be consulted cannot be consulted.

	Habermas isn't a monument to German stupidity - more like a bumper
sticker.

Book Report

  My book report follows, but now I
offer him the assignment of reading Aaron Sloman's "The Computer
Revolution in Philosophy" and giving us a book report.


	Finally, let's return to the requirements in AI.  I explained
in a previous message why Robby needs a predicate  true(x)  applicable
to assertions, and it doesn't matter much whether the domain
of the predicate is taken as sentences or some more abstract object.
Remember that quantified assertions about truth are required in
order express opinions about the reliability of people and programs.
A dozen or two axioms about truth will suffice for Robby's requirements.
Robby has no need for a theory of speech acts; he needs the
predicate  true  even if he will never speak or listen and doesn't
know about other persons at all.

	However, a theory of human speech acts would have some value
if correct, although I think it has started off on the wrong two
hundred feet.  GAVAN is hereby challenged to extract from Habermas
a formalized theory useful for Robby.

	Habermas refers to a "correspondence theory of truth"
but I didn't recognize his caricature as resembling either my
own views or those described in the Encyclopedia of Philosophy
article.

	Perhaps one could apply Schopenhauer's remark here,
although instead of a monument one might imagine a bumper sticker.

Additional remarks:

	Putnam's discussion of the similitude theory of correspondence
ignores facts which Putnam knows quite well, presumably because
Putnam has gone into history-of-philosophy mode in which it isn't
customary to mention them.  First there is nothing problematical
about the relation between a red object and our mental image of
it.  Computers with TV cameras and even video tape recorders
store images of red objects in suitabe data structures.  No-one
imagines that the spots on a magnetic tape are similar like a
red object.  Likewise for a long object.  It's hard to see why
Putnam doesn't bring his discussion into the twentieth century.
Indeed his discussion became obsolete in the 1880 when Edison
invented the phonograph.

	The discussion is also innocent of the various kinds
of correspondence studied in mathematics, and I believe that
Putnam has at least as much technical knowledge of mathematics
as I do and more technical knowledge of logic.  Homomorphism
anyone?

	The considerations that Habermas and Putnam have advanced
are very complex and not at all formal.  Anything that complex
is likely to have a bug in it somewhere.  It isn't a very
satisfying activity to try to find out where, because
many of the concepts are so vague that it is impossible to
tell which step is the non sequitur.  Fortunately, for
computer scientists and engineers there is an alternative.
This is to start with simple systems and build from there.

	In the present case we must ask what is problematical
about a thermostat's representation of the temperature in the
room.  If nothing, and I think that's the answer, then what is
essentially different between a thermostat's representation of
the temperature and my representation of the desk before
me.  It's just another data structure which can be regarded
as representing information about the world.
Book Report

	At GAVAN's instigation, I have read the translated chapter of
Jurgen Habermas's "Theories of truth", which he kindly supplied, and
Hilary Putnam's chapter "Two Philsophical Perspectives" reprinted in his
book "Reason Truth and History".

	The first concerns the consensus theory of truth and the second
concerns an "internal realist" or coherence theory of truth.  He hoped
that they would make me reconsider my adherence to a correspondence theory
of truth.  I read them hoping for information relevant to making computer
program reason about their own knowledge or to helping computer scientists
reason about computer programs.  As you may remember from previous
messages, I believe that Robby will need the predicate true as applied to
sentences (or more abstract entities called propositions).

	Often I have found theories developed by epistemologists
useful in AI.  Examples include the  de re - de dicto  distinction,
modal logic, and the concept of natural kinds, the latter a subject
to which Putnam has made contributions.  Unfortunately, I could
not find anything usable in either of the present papers.  I think
AI will have to start almost from scratch in building a theory of
the relation between minds and the world.

	I will begin with Habermas, proceed to Putnam, and then
recapitulate why AI needs a theory of little minds in little
worlds and requires what I would describe as a correspondence
theory.


Habermas:

	Habermas offers a consensus theory of truth, the best summary
of which is the following paragraph.

     "On this view I may ascribe a predicate to an object if and only if
     every other person who could enter into a dialog with me would also
     ascribe the same predicate to the same object.  In order to
     distinguish true from false statements I make reference to the
     judgments of others -- in fact to the judgment of all others with
     whom I could ever hold a dialog (among whom, contrary to fact, I
     include all the dialog partners I could find if my life-history were
     coextensive with the history of mankind).  The condition of the truth
     of statements is the potential agreement of all others.  Every other
     would have to able to be convinced that I am justified in ascribing
     to object x the predicate p and would then have to be able to agree
     with me.  Truth means the promise of attaining a rational consensus".
	- from page 7 of the anonymous translation.

	This is certainly different from the common sense notion
of truth, from Tarski, and from my own opinion.  According to us,
everyone who ever lived could be mistaken about some question.
Moreover, an assertion or proposition or sentence could be true
if no-one ever thought of it, since truth is a relation between
assertions and the world and has nothing to do with whether anyone
ever thinks of it.

	Habermas's notion of truth is imbedded in a theory of
speech acts - a mess for which John Searle of Berkeley bears
a substantial part of the responsibility.  Exhibiting this mess
is the following citation from page 6.

     "We can summarize the results of our preliminary deliberations in
     three theses, which require further explication.

     1. We call truth the validity-claim which we associate with
constative speech acts.  A statement is true if the validity-claim of the
speech acts by means of which, in employing sentences, we maintain that
statement is justified.

	2. Questions of truth arise only if the validity-claims naively
imputed in contexts of action become problematic.  In discourses where
hypothetical validity-claims are tested, utterances about the truth of
statements are therefore not redundant.

	3. In contexts of action assertions give information about objects
of experience; in discourses stements about facts are discussed.
Questions about truth are consequently raised not so much in reference to
the inner worldly correlates of action - with discourses that are
experience -- and action -- free.  Whether states of affairs are or are
not the case is not decided by experiential evidence, but by the course of
argument.  The idea of truth can be unpacked only in reference to the
discursive settlement of validity claims.

	From these theses I would like to draw a few provisional
conclusions which suggest a consensus theory of truth."

	The above citation contains the following terms all of which are
treated as technical terms of his theory: truth, validity-claim,
statement, justified, naively imputed, contexts of action, utterance,
assertion, discourse, facts, information, inner worldly correlate, action
related cognition, experience, experiential evidence and course of
argument.  This is just the beginning; the number of technical terms in
this paper must exceed a hundred.  It would be unfortunate but ok if
they were really needed to understand what truth is.  However, my opinion
is that Habermas, no doubt with help from other obscurantist philosophers
like Searle, is in a mode whereby he keeps adding terminology in order to
try to get out of complications induced by the preceding terminology.

	I fear that GAVAN will feel cheated by the fact that I decline
to make an analysis of this paper and prefer to make a few superficial
remarks about the views expressed and then start over.  My reason is
that there isn't time.  Each term would require a page of speculation
about what it might mean and each sentence would require another page
of analysis.  A whole 500 page philosophy PhD thesis could be written
about this one paper, and many have about similarly obscure writings
of more famous philosophers.


Putnam:

	Putnam is a lot more comprehensible than Habermas.  and his "Two
philosophical perspectives" seems to be where GAVAN got his "God's eye
view" epithet.  Putnam's argument has the following character.  If the
correspondence theory were true, we would have to admit that we might be
brains in a vat connected electronically to the outside world.  But then,
and I elide his argument a great deal, how could we really be referring to
the external world.  In other words, metaphysical realism faces a
difficulty in referring.

	The argument is intricate, but fortunately it is possible
to say, "So what?".   There may indeed be difficulties in referring.
The Life World physicists may be harassed by a life world Putnam
(not to speak of a Life World GAVAN) claiming that their hard won
conjecture that their fundamental physics is a certain two dimensional
cellular automaton is a just a way of referring to a coherent set
of sentences.  However, we, with our God's eye view of the Life
World, congratulate the Life World physicists on their success.

	To repeat my previous argument.  There is nothing about
evolution that guarantees that creatures who evolve intelligence
will have an easy time with epistemology.  In the words of a
Moroccan proverb, "The world has not promised anything to anybody".

	If I understand Putnam correctly, this makes me an even
more extreme externalist than his straw man.  Putnam's straw man
externalist relates terms to things they refer to by some kind of
causal chain.  In my view, the world has not promised that there
will be a causal chain between me and all objects that exist,
because there is no law that prevents intelligence from evolving
in a way that leaves it causally cut off from some aspect of
the world.  Tough for us.  We can't be sure that what we can
possibly discover about science, geography, history
or even mathematics is all there is.


The God's eye view - beginning with little minds in little worlds

	Putnam accuses "external realists" of advocating a God's
eye view, and Gavan has accused me of arrogance in this connection.
After reading Putnam's paper, I have concluded that this is an
excellent short description of what I advocate.

	Putnam's paper summarizes the history of the philosophy of
reference - e.g. the relation between red or long objects and what
represents them in the mind or brain.  The history includes Aristotle,
Plato, Locke, Berkeley, Kant, Wittgenstein and Nelson Goodman.
Locke begins by arguing that whatever may correspond to a red object
in the brain, it isn't red - thus criticizing his predecessors, and
his successors jazz up this idea.  Indeed.

	Starting with a very little mind, we can also say that whatever
corresponds to a temperature of 72 degrees in a thermostat, it isn't
a temperature.  Whatever corresponds to a red apple in the memory
of a computer connected to a TV camera isn't red, isn't round and
isn't tasty.  What makes the relation between the data structure
in a person's brain and the objects he sees more problematical?
Nothing except that a human is discussing the relation.  We will
face complications when we design a computerized thermostat that
reasons about whether its opinion of the temperature is justified.

	Actually there are difficulties in designing an AI system
that can reason about the towers of blocks it sees on the table
with its TV camera.  For example, I am having difficulty devising
a formalization that will include abstract designs (a red block on top of
two green blocks), concrete but unrealized designs (block A on
top of block E and block F where these blocks are a red and two
greens), realized designs existing in a the present or some
hypothetical situation.  There is also the problem of a tower
retaining its identity while it is being improved, i.e. having
blocks added to it.  Unfortunately, nothing Habermas or Putnam
has anything to say relevant to how we must go beyond the
concepts required to understand the simple thermostat in order
to represent facts about the blocks world.

	The problem of the relation between information in the
human brain and phenomena in the world is much more complex than
the above-mentioned blocks world that already gives us difficulties.
However, I don't believe that Habermas or Putnam even intend to
help with it.  If you have doubts, go back to the above Habermas
extracts and ask how they help with the blocks world or even
with the thermostat.  If you believe in the relevance of all those
Habermas concepts, consider writing a LISP program to use them
for some practical purpose.

	Unfortunately, this kind of philosophical discussion tends to
distract attention from the real, practical and interesting problems of
epistemology.  Indeed the amount of thought already put into the PHIL-SCI
discussion might make a dent in the blocks world problem if it weren't
being dissipated.

	Now that I have done a book report on two opuses suggested
by GAVAN, let me suggest to him that he do one on Aaron Sloman's
"Computer Revolution in Philosophy".  I fear he won't like it any
better than I liked Habermas, but it will be more productive than
a paragraph by paragraph refutation of the foregoing.  I don't agree
with even most of what Sloman says, but it has quite a number of
interesting and useful ideas.
Addendum to book report

	Indeed there are sometimes too many correspondences - equivalent	
as to observable consequences.  Putnam's example is the equivalence
between wave theories of electricity and magnetism and
action-at-a-distance theories.  The truth may be one or the other
or neither.  It may also be that there may be such an isomorphism
that a more abstract view is desirable.  The problem is mitigated
by the fact that assertions like, "This electron exerts .01 dynes
repulsion on this other electron" are the same in both theories.
Again we must distinguish between what may or may not be true
and what we may or may not have the opportunity to determine.
Such grand problems won't arise soon with Robby.