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- Path: sparky!uunet!usc!venice!doc.bmd.trw.com!jbrown
- From: jbrown@doc.bmd.trw.com
- Newsgroups: alt.atheism
- Subject: Re: Constructing a Logical Argument
- Message-ID: <1993Jan22.084501.592@doc.bmd.trw.com>
- Date: 22 Jan 93 08:45:01 MST
- Lines: 91
-
- Newsgroups: alt.atheism
- Subject: Re: Constructing a Logical Argument (long)
- Message-ID: <1993Jan22.072510.20684@blaze.cs.jhu.edu>
- From: arromdee@jyusenkyou.cs.jhu.edu (Ken Arromdee)
- Date: Fri, 22 Jan 1993 07:25:10 GMT
-
- In article <1993Jan21.190024.591@doc.bmd.trw.com> jbrown@doc.bmd.trw.com writes:
- >"A flood as described in the Bible would require an enormous volume of water
- >to be present on the earth. The earth does not have a tenth as much water,
- >even if we count that which is frozen into ice at the poles. Therefore no
- >such flood occurred."
- > Your statement above, intended to illustrate Denial of the Consequent
- > (if I have my terms correct), actually includes the fallacy of hidden
- > assumptions. The hidden assumption is that the topography of the earth
- > has not significantly altered since just before the time of the Flood.
- > Actually, we do not know if such a change occurred or not.
-
- If what you have pointed out is indeed a fallacy, consider that an argument
- about the roundness of the earth contains the hidden assumption that light
- doesn't bend in exactly the way to make the flat earth look round from space,
- the hidden assumption that the people who claim to have circumnavigated it
- are not lying, etc.
-
- I didn't say that hidden assumptions constitute lying. Nor are the
- two cases strictly analogous. When one says that "the earth is round",
- it means that the earth approximates a sphere in shape, although not
- exactly, the diameter through the equator being some miles longer than
- the diameter through the poles. What you state as a "hidden assumption"
- concerning circumnavigation is not at all a hidden assumption in the
- logical sense as I used it above. Of course, at the time that Magellan
- first circumnavigated the globe, one might have asserted that the report
- of the acting captain surviving Magellan was erroneous, and that any
- argument assuming the truth of the report included a hidden assumption.
- However, at the time, there was an independent body of evidence from
- other voyages which would generally corroborate the truth of Magellan's
- voyage even though it was the first true circumnavigation.
-
- This is not at all analogous to the situation I mention, since there is
- little evidence other than the various flood accounts as to the state of
- the earth at the time in question. Certainly geologists have well
- thought-out theories as to what has happened to the earth in the past,
- but these are still essentially "educated guesses" and not factual
- observation. Therefore to assume that the earth's topography was not
- different at the time of the Flood, however reasonable it may seem,
- constitutes a flaw in the argument. Especially since the conclusion
- definitely states that there is no chance that the Flood could have
- occurred. Not little chance, but *no* chance. The strength of the
- argument is overstated as a result.
-
- A hidden assumption that something did _not_ happen is not a hidden assumption
- at all; the burden of proof is on you to prove that something happened.
-
- --
- Ken Arromdee (arromdee@jyusenkyou.cs.jhu.edu, arromdee@jhunix.hcf.jhu.edu)
-
-
- If there is outstanding evidence to support the hidden assumption such
- that it can be considered to be "generally accepted", then it can "go
- without saying", but one still runs the risk of forming an incomplete
- argument. This may or may not be significant depending on the
- audience and their acceptance of what "goes without saying". If the
- hidden assumption or unstated premise is only "generally accepted"
- among those of the same school of thought, then it is a logical flaw
- not to state and support the premise in an argument directed at those
- outside that school.
-
- And furthermore, the "burden of proof" is not on me at all. In my
- discussion above I made no assertion that the Flood occurred or that
- the earth's topology actually changed. I stated that it was a
- possibility, and thus the prior argument as stated was invalid.
- I do not have to assert, and thus substantiate, a possible event as
- having occurred, I only have to consider the possibility in order
- to *disbelieve* the argument as stated and to reject the strength
- of the argument as contained in the statement "...no such flood
- occurred."
-
- This is exactly analogous to the "I disbelieve in god(s)" vs. the
- "I believe there are no gods" distinction that you and others here
- in a.a. like to make. The first statement makes no assertions about
- god(s), but simply does not accept the assertions of others. There-
- fore there is no burden of proof. The second statement makes an
- assertion in the negative, and therefore carries a burden of proof.
-
- Logic cuts both ways, it seems.
-
- Regards,
-
- Jim.
-
- Please send replies or comments to: Jim_Brown@oz.bmd.trw.com
-
-