mark@umcp-cs.UUCP (Mark Weiser) (09/23/86)
So can one have a consistent system in which A and not A are both true?
Well, not in the technical sense of consistent, because it is defined
to NOT mean this. So change consistent to mean workable, practical,
inspiring, enlightening. Now what does it mean to say A and not A are
both "true"? True is slippery concept here. If true is defined as
follows: "'A' is true iff A", assuming all the appropriate temporal
and situational caveats, then again a technical problem confronts
us in the meaning of 'iff', which will not permit both A and not A
to appear in the above definition and make sense. So change truth
to mean: 'part of the possible existence of people". NOW can
both A and not A be true? Sure, you bet, even within the same person,
and I don't mean trivially because people can disagree.
A and not A can both be true, in a consistent system, within the definitions
above, because both A and not A are in fact always present. There is
no A without not A (every foreground has its background, else it
is not present at all). Therefore in a profound sense EVERY system must
have both A and not A true, else it has nothing in it at all.
(The above is loosely based on a long association with the thought of Heidegger.
I am responsible for the content, not him. He's dead, after all.)
-mark
--
Spoken: Mark Weiser ARPA: mark@maryland Phone: +1-301-454-7817
CSNet: mark@umcp-cs UUCP: {seismo,allegra}!umcp-cs!mark
USPS: Computer Science Dept., University of Maryland, College Park, MD 20742ladkin@kestrel.ARPA (Peter Ladkin) (09/24/86)
In article <3539@umcp-cs.UUCP>, mark@umcp-cs.UUCP (Mark Weiser) writes: > [.....] So change truth > to mean: 'part of the possible existence of people". ?????????????????????????????????????????????????????? Peter Ladkin ladkin@kestrel.arpa
cc100jr@gitpyr.UUCP (Joel Rives) (09/24/86)
In article <3539@umcp-cs.UUCP> mark@umcp-cs.UUCP (Mark Weiser) writes: >A and not A can both be true, in a consistent system, within the definitions >above, because both A and not A are in fact always present. There is >no A without not A (every foreground has its background, else it >is not present at all). Therefore in a profound sense EVERY system must >have both A and not A true, else it has nothing in it at all. > >(The above is loosely based on a long association with the thought of Heidegger. If you find value in this way of thinking then I recommend that you read some on Taoist philosophy. -- Joel Rives gatech!gitpyr!cc100jr { * }-------{ * }-------{ * }-------{ * }-------{ * }-------{ ^ }-------{ * } There is no place to seek the mind; It is like the footprints of the birds in the sky. { * }-------{ * }-------{ * }-------{ * }--------{ * }-------{ * }-------{ * }
mark@umcp-cs.UUCP (Mark Weiser) (09/26/86)
In article <12726@kestrel.ARPA> ladkin@kestrel.ARPA (Peter Ladkin) writes: >In article <3539@umcp-cs.UUCP>, mark@umcp-cs.UUCP (Mark Weiser) writes: >> [.....] So change truth >> to mean: 'part of the possible existence of people". > >?????????????????????????????????????????????????????? > >Peter Ladkin >ladkin@kestrel.arpa Oh, I bet you are one of those who likes: "'P' is true just if P" for your definition of truth (Tarski). I find this definition rather silly as it leaves out just about all the hard questions, and furthermore only applies when there is language, or worse, logic. Long before there was language there was truth and falsity: for instance, the pre-linguistic hunter/gatherer on a false trail or a true trail in the woods. Before there can be a P, much less a 'P', there has to be the possiblity of experiencing the world. That is why 'truth' as 'part of the possible existence of people', while just a shorthand expression, is a lot closer to what truth really means than the logicians definition. If you want to know more, check out one of the most influential philosophers of the 20th century, Martin Heidegger. With particular regard to truth, try: "On the Essence of Truth", in Existence and Being, published by Regnery, Chicago (1949). -mark -- Spoken: Mark Weiser ARPA: mark@maryland Phone: +1-301-454-7817 CSNet: mark@umcp-cs UUCP: {seismo,allegra}!umcp-cs!mark USPS: Computer Science Dept., University of Maryland, College Park, MD 20742
janw@inmet.UUCP (09/26/86)
[Mark Weiser: mark@umcp-cs.UUCP ] >A and not A can both be true, in a consistent system, within the >definitions above, because both A and not A are in fact always >present. There is no A without not A (every foreground has its >background, else it is not present at all). Therefore in a pro- >found sense EVERY system must have both A and not A true, else it >has nothing in it at all. >(The above is loosely based on a long association with the >thought of Heidegger. This is basically Hegel's teaching on the matter, although he would not have used the words *consistent system* (something closed and static), and especially, *a* system - since that makes truth a matter of convention. To him, "truth is a process", and an objective one. The idea of "A" not only presupposes "not A" as background, but changes the "system" to call not-A forth. Paraphrasing Heraclitus, you cannot enter the same system twice. On second thoughts, I'd better say (still in a Hegelian mode but not using his vocabulary): you cannot enter the same *context* twice - and it is more inevitable than with Heraclitus's river. Water might stop flowing; but your very entering a context changes it. Now, in what direction does thought change its context? To quote Mark Weiser again, >Therefore in a profound sense EVERY system must have both A and >not A true, else it has nothing in it at all. According to Hegel, thought evolves in the direction of this "profound sense": a synthesis of the opposites inherently present in the "system" - he would have said, in Reality, being a (lowcase o) objectivist - is, step by step, realized by the pro- cess of pure thought. Each A evolves into some not-A and then into some <A & not-A> - which was implicitly there all along. "Only in the end is a thing what it is in truth" (Hegel). Thus, in place of the "system" of Mark Weiser, there is the real- ity inquired into, and the inquiring thought - but according to Hegel, in the end, the two merge. Reality is fully knowable because it's made of the same stuff thought is. The time implied in this process of truth is logical time, not the time of nature - but (this is another story) it is, according to Hegel, also the time of human history. [Based on a long-term but long-past acquaintance with Hegel's thought. The books to read are the Phenomenology of the Spirit and the larger Logic. A good translation is essential. Hegel uses the language in many non-obvious ways.] Jan Wasilewsky
ladkin@kestrel.ARPA (Peter Ladkin) (09/27/86)
In article <3591@umcp-cs.UUCP>, mark@umcp-cs.UUCP (Mark Weiser) writes: > Oh, I bet you are one of those who ..... ......was completely puzzled by what you meant. > That is why 'truth' as 'part of the possible existence of people', > while just a shorthand expression, is a lot closer to what truth > really means than the logicians definition. How about giving the longhand definition instead? I still find the shorthand incomprehensible. About Heidegger, have you read any of Dreyfus's commentaries? Peter Ladkin ladkin@kestrel.arpa
mark@umcp-cs.UUCP (Mark Weiser) (09/27/86)
In article <2282@gitpyr.UUCP> cc100jr@gitpyr.UUCP (Joel Rives) writes: > >If you find value in this way of thinking then I recommend that you read some >on Taoist philosophy. > I have read some Taoist philosophy. I find Heidegger more satisfying because he has to wrestle with the entire Western philosophical tradition, not ignore or dismiss it. Thus I can read Heidegger on Kant, on Aristotle, on various pre-Socratics, on philosophy of science and art. -mark -- Spoken: Mark Weiser ARPA: mark@maryland Phone: +1-301-454-7817 CSNet: mark@umcp-cs UUCP: {seismo,allegra}!umcp-cs!mark USPS: Computer Science Dept., University of Maryland, College Park, MD 20742
belmonte@svax.cs.cornell.edu (Matthew Belmonte) (10/11/86)
In article <117400049@inmet>, janw@inmet.UUCP writes: > Paraphrasing Heraclitus, you cannot enter the same system > twice. No, that's paraphrasing Plato's misinterpretation of Heraclitus. Plato said that Heraclitus said that "you could not step into the same river twice." The real fragment is "Upon those who step into the same river flow other and yet other waters." I think Heraclitus must be one of the most misinterpreted philosophers. The same river continues to exist as such, but its composition changes. It becomes warmer and cooler as the seasons change. It may flow into a desert or sea somewhere and cease to exist as such. The _logos_ is in constant flux. There is opposition in everything. But things can change in their accidental properties and still remain what they are (were). It is only when the set of essential properties no longer fits the definition of thing that new-thing has ceased to be thing. We don't define "river" as containing certain waters or containing waters of a certain temperature. (Please no flames about water's freezing and boiling depending upon temperature; I'm saying "certain temperature," not "certain temperature range.") Therefore, when a river warms or cools or flows we still believe that it's the same river. A final comment about _A_ and "not _A_" -- let's be sure what we mean by "not _A_." Define the set B as - {A} if A is an individual (Yes, I know this is debatable for most A.) - A if a is a set By not-A, we could mean "the opposite of A" or we could mean, more generally, the set U-B, where U is the universe. Unless the universe is restricted to A and its opposite, then these two interpretations are not equivalent. -- Matthew Belmonte ARPA: <belmonte@rocky.cs.cornell.edu> <belmonte@svax.cs.cornell.edu> BITNET: <d25y@cornella> <d25y@crnlvax5> UUCP: ..!decvax!duke!duknbsr!mkb