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Carl Cohen, Copi's co-author, confirms it -- "Goliath" is valid!

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  • w_w_c_l
    ... Let s see... There is one more relevant quote from the 11th edition of *Introduction to Logic*, by Irving M. Copi and Carl Cohen, that was not in the older
    Message 1 of 18 , Jan 1, 2008
      --- In Maury_and_Baty@yahoogroups.com, "w_w_c_l"
      <w_w_c_l@...> wrote (in conclusion):
      >
      > The above material, coupled with the previously posted material
      > from the 11th edition of *Introduction to Logic*, along with
      > the numerous other references and resources that have been
      > archived over the last several months, should put to rest once
      > and for all any question about the formal logical validity of
      > Robert's syllogism, reproduced below.
      >
      > There's just one more thing... ;-)

      Let's see...

      There is one more relevant quote from the 11th edition of
      *Introduction to Logic*, by Irving M. Copi and Carl Cohen,
      that was not in the older edition we have been referencing.

      Jerry McDonald neglected to mention it to us, but our friend
      who has been providing us with the previously posted material
      from the 11th edition (which we had asked McDonald for, and
      were unable to get him to produce) found the following quote,
      and acted upon it:

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

      | Acknowledgements
      |
      | The loyal support of instructors and students of logic
      | has been a major factor in the steady improvement of
      | "Introduction to Logic" over the years. This widespread
      | (and sometimes critical!) participation of our readers
      | has proved to be a mighty strength. To all of those who
      | have had some role, large or small, in molding this
      | eleventh edition, we convey our hearty thanks.
      |
      | Readers who offer their suggestions (email: ccohen[at]umich.edu)
      | receive our direct response, of course; but we also take
      | satisfaction in listing here the names of some of those to
      | whom we are indebted.

      (snip, snip)

      | Irving M. Copi
      | University of Hawaii
      |
      | Carl Cohen
      | University of Michigan, Ann Arbor

      Introduction to Logic
      pages xix-xxi

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


      Did somebody say e-mail? I think they did!

      Well, why didn't Jerry McDonald say so, knowing, as he
      does, our interest in contacting the logic experts at
      various colleges and universities and asking them for
      their professional opinion on the formal logical validity
      of "Goliath"!

      Anyway, no harm done!:

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


      From: Robert Baty
      Sent: Wednesday, December 19, 2007 10:25 PM
      To: Carl Cohen
      Subject: Introduction to Logic query!

      Dear Professor Cohen,

      I have been involved in recent, quite heated discussions
      with some who have sought to use your and Copi's text in
      support of the proposition that the following is not a
      simple, logically valid, modus ponens argument:

      > Major premise:

      > If God's word (the text) says
      > everything began over a period
      > of six days, is interpreted by
      > some to mean it was six 24-hour
      > days occurring a few thousand
      > years ago, and there is empirical
      > evidence that some thing is
      > actually much older than a few
      > thousand years, then the
      > interpretation of the text by
      > some is wrong.

      > Minor premise:

      > God's word (the text) says
      > everything began over a period
      > of six days, is interpreted by
      > some to mean it was six 24-hour
      > days occurring a few thousand
      > years ago, and there is empirical
      > evidence that some thing is
      > actually much older than a few
      > thousand years.

      > Conclusion:

      > The interpretation of the text
      > by some is wrong.

      By my way of thinking and interpreting your text, they are
      simply wrong in their use of various statements from your
      text.

      It would be helpful if you could give me your opinion, for
      the record, as to the simple, logical validity of the above
      stated argument.

      Do you consider the above argument valid?

      Any exposition regarding your answer will be welcomed and
      helpful.

      A speedy reply would also be much appreciated.

      Sincerely,
      Robert Baty
      Ft. Collins, CO


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

      After receiving an automated response saying that
      Professor Cohen would be vacationing in Dominica until
      after Christmas, and posting a follow-up query, Robert
      received the following reply:

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


      To: Robert Baty
      From: Carl Cohen
      Subject: Re: Introduction to Logic query!
      Date: Monday, December 31, 2007 3:20 PM

      Carl Cohen
      Philosophy
      The University of Michigan

      31 December 2007

      To Whom It May Concern:

      I don't know the persons I am here addressing, but I do
      hope that I may be helpful:

      An argument in the form of ~modus ponens~ is indubitably
      valid, and can be proved valid on a truth table, as we do
      in *Introduction to Logic*.

      Its logical form is:

      p > q,
      p,
      therefore q.

      In English this might be stated as:

      "If some hypothetical proposition asserting that 'if p then q'
      is true, and a second proposition asserting 'p' is true, then
      we may certainly conclude that 'q' is true."

      The content of 'p' and the content of 'q' is of no consequence
      whatever; the argument is valid in virtue of its form alone.

      Thus, for example, if it is true that

      > "If there is a green fairy on
      > my desk then I will be in
      > Timbuktu tomorrow,"

      and if it is also true that

      > "There is a green fairy on
      > my desk"

      then it follows irrefutably that

      > "I will be in Timbuktu tomorrow."

      The compelling logical force of ~modus ponens~ arises from
      the formal relations between 'if p then q', 'p', and 'q'.

      The statement variables 'p' and 'q' may be replaced by
      any propositions whatever.

      Turning then to the argument that has been sent to me
      for comment:

      Let us suppose that the variable 'p' is replaced by
      the following proposition:

      > "God's word (the text) says
      > everything began over a period
      > of six days, is interpreted by some
      > to mean it was six 24-hour days
      > occurring a few thousand years
      > ago, and there is empirical evidence
      > that some thing is actually much
      > older than a few thousand years."

      Let us suppose that the variable 'q' is replaced by
      the following proposition:

      > "The interpretation of the text
      > by some is wrong."

      IF it is true that the proposition 'p' just above
      entails the proposition 'q' just above, [p > q]
      AND if it is true that 'p', [p]
      then 'q' is most certainly true. [q]

      The truth of the conclusion [q] is here established only if
      we know the hypothetical proposition [p > q] to be a true premise,
      and know also that the antecedent within the hypothetical [p]
      to be a true premise.

      ~Modus ponens~ tells us absolutely nothing about the truth of
      these premises; it is a valid argument FORM. It states only that
      IF p > q, AND p, THEN q.

      I hope this is helpful.

      Have a satisfying new year.

      Be well.
      Carl Cohen


      -----------Robert Baty wrote:------------
      >
      > Dear Professor Cohen,
      >
      > I hope that you have now been able to return as planned
      > from Dominica and will be making responses to your
      > backlogged e-mail as anticipated.
      >
      > Pending your hoped-for attention to my inquiry, I have
      > again thought it might be helpful to give you yet another
      > example of how Jerry McDonald has attempted to use your
      > "Introduction to Logic" to support his false claim regarding
      > the simple, logical validity of my argument which I presented
      > for your consideration in my two earlier e-mails; copies of
      > which follow my name below.
      >
      > Here is a link to a message posted by Jerry McDonald regarding
      > this matter, with relevant excerpts therefrom:
      >
      > -----------------------------
      >
      > http://groups.yahoo.com/group/Maury_and_Baty/message/12987
      >
      > Maury_and_Baty YAHOO! discussion list
      > Message #12987
      >
      > From: Jerry McDonald
      > Date: October 27, 2007
      >
      > Subject: Re: Response To Todd Greene
      >
      > (excerpts)
      >
      >| If "P" then "Q"
      >| "P"
      >| Therefore "Q".
      >|
      >| "Q" must irrefutably follow from "P."
      >|
      >| If it doesn't then regardless of the form it isn't valid.
      >|
      >| If makes absolutely no difference what form you use, if
      >| the conclusion is not irrefutably drawn by the premise,
      >| the argument is invalid.
      >|
      >| You said, earlier, that I was not looking at everything
      >| else that Copi said, but I was.
      >|
      >| It was you who were not looking at everything.
      >|
      >| You left out that parenthetical phrase about constituent
      >| and contingent. You said it wasn't in the fourth edition.
      >|
      >| I don't have that edition so I cannot say for sure. However,
      >| it was in the fifth through the 11th.
      >|
      >| The word "constituent" means that the two premises must be
      >| so related if they are both true the conclusion must
      >| necessarily be true.
      >|
      >| The validity of the argument is contingent upon the
      >| constituency of the premises and conclusion.
      >|
      >| Again my argument:
      >|
      >| Major Premise:
      >|
      >| If the cow jumps over the moon, then the moon is
      >| made of cream cheese.
      >|
      >| Minor Premise:
      >|
      >| The cow jumped over the moon.
      >|
      >| Conclusion:
      >|
      >| The moon is made of cream cheese.
      >|
      >| Now it is in the proper form "If P then Q", "P",
      >| "therefore Q."
      >|
      >| However, there is no relation between the conclusion
      >| and the premise.
      >|
      >| Just because the cow jumps over the moon this does not
      >| necessarily and irrefutably mean that the moon is made
      >| of cream cheese.
      >|
      >| There has to be such a relation between the premise and
      >| the conclusion that if the premise is true it is axiomatic
      >| that the conclusion be true as well.
      >|
      >| Baty's argument doesn't do this, there are too many holes
      >| in it to keep the conclusion from being irrefutably true
      >| if the premises are true.
      >|
      >| In Christ Jesus,
      >| Jerry McDonald

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


      So there you have it, folks!

      Carl Cohen "indubitably" illustrates for us why Robert's
      syllogism is formally valid. He irrefutably refutes
      McDonald's misguided notions that 'q' must follow from 'p'
      for an argument to be formally valid and that validity is
      dependent on any other thing besides form alone.

      As Robert Baty might say (and did!):

      > "We win!"
      >
      > "We win!"


      Great work there, Robert! And thanks for looking up those
      quotes for us -- the ones that Jerry McDonald is claiming he
      gave us, knowing full well he never did!

      Let's see -- that makes it 15-0 for "Goliath" against the
      unsuccessful attempts of Jerry McDonald, and Terry Hightower
      and the rest of David (not "David") P. Brown's "boys"!

      Undefeated! I'll be posting the season statistics shortly,
      as a follow-up to this message.



      Rick Hartzog
      Worldwide Church of Latitudinarianism
    • Todd S. Greene
      Yes, Jerry, we know you re incapable of comprehension (this is the aspect of incompetence that you yourself told me I was neglecting to mention about young
      Message 2 of 18 , Jan 4, 2008
        Yes, Jerry, we know you're incapable of comprehension (this is the
        aspect of incompetence that you yourself told me I was neglecting to
        mention about young earth creationists), and of acknowledging even
        obvious errors and then making the necessary corrections to your
        thinking and then changing your statements as necessary to take
        account of the necessary corrections.

        Cohen told you you were wrong. He even took the time to explain why
        you were wrong. (Robert, Rick, and I had also already previously told
        you exactly what Cohen told you. Geeze, even with the moon and cream
        cheese argument example you posed, all of us told you exactly the same
        thing, even Cohen has now told you explicitly exactly what Robert,
        Rick, and I had *already* told you and explained in detail to you
        several times. But you continue to show yourself absolutely incapable
        of acknowledging and correcting your error.)

        Yet there is something about your personal attitudes (mixed in with a
        bunch of religious dogma) that you are so mired in your rhetoric and
        lack of comprehension, and your many errors, that you refuse to clean
        up your act. You behaved in this same manner with all of the other
        errors pointed out to you, including your erroneous claim that Capaldi
        is an atheist.

        What your behavior, the deliberate nature of it, proves by example is
        that you are a man who is apparently unable to comprehend what he
        preaches about and who has also dedicated himself to lying to people
        on these subjects, showing that you do not engage in such discussions
        due to any interest in the truth of the matter.

        The only time I waste on you is when I feel that the public record of
        your behavior is beneficial to showing everyone the incompetent and
        deceitful nature of your rhetoric, incompetence and deceitfulness that
        is endemic to young earth creationist rhetoric.

        - Todd Greene


        --- Jerry McDonald wrote:
        > Then since I am so incapable, why do you waste your time
        > with me Todd? I am incapable of change, so don't bother
        > me.
        >
        > jdm
        >
        >
        > Todd Greene wrote:
        >> Poor Jerry, I do feel sorry for you sometimes. Your
        >> thinking is so hopelessly confused and muddled it's a
        >> wonder you waste your time attempting to engage in
        >> rational discussions like these.
        >>
        >> Robert stated the FACT that you were misusing Cohen's
        >> (and Copi's) words, because you were. You did. This is a
        >> fact, and it's a matter of public record. So your
        >> attempt to claim otherwise is simply more of the typical
        >> deceitful rhetoric we've come to expect from you.
        >>
        >> You wrote, "However, as you [Cohen] have stated in order
        >> for me to question the validity of Robert's argument
        >> then I must show that one of the premises is not true."
        >>
        >> No, that's not what he said. This is like when Robert
        >> and Rick and I would point out something to you, and
        >> explain it to you in detail, three, four, five, six or
        >> more times, and you'd come right back with comments
        >> proving that you were utterly incapable of comprehending
        >> what you were being told.
        >>
        >> If you show that one of the premises is not true, then
        >> you are showing that the argument is UNSOUND, not
        >> invalid. In such a case, you would not be questioning
        >> the *validity* of the argument, you would be questioning
        >> the *soundness* of the argument. I have zero doubt that
        >> you are not capable of comprehending the distinction
        >> between logical validity and soundness, but I have to
        >> reiterate your error on this point.
        >>
        >> You also wrote, "Therefore, if something has been found
        >> to be, say 3 billion years old, then either the dating
        >> process is wrong, or the Bible is wrong; not the
        >> interpretation of the Bible. That is where Baty's
        >> argument becomes invalid."
        >>
        >> Jerry, you are simply wrong. Yet again. It has become
        >> absolutely obvious that you are incapable of
        >> understanding this. You need to cease making such false
        >> statements. Your error has been pointed out and
        >> explained to you several times by different people.
        >> Regardless of the fact that you are simply not capable
        >> of understanding this, that you continue to promote your
        >> error is how you show us your attitude of deceitfulness,
        >> that you will continue to promote error regardless of
        >> the facts (whether you understand the facts or not; now
        >> even a specific logician you falsely represented has
        >> written and told you that you are wrong).
        >>
        >> If the first premise of GRAS is incorrect, then the
        >> argument is UNSOUND, but not invalid. Where you write
        >> "That is where Baty's argument becomes invalid" is where
        >> you show - yet again - that you simply don't know what
        >> you're talking about.
        >>
        >> And that's about par for the McDonald course.
        >>
        >> - Todd Greene

        ================================================================

        --- Jerry McDonald wrote:

        Dr. Cohen

        I will certainly take your advice under consideration.

        However, as you have stated in order for me to question the
        validity of Robert's argument then I must show that one of the
        premises is not true. I do question the major premise because
        the conclusion does not irrefutably follow from the premises. I
        realize that you are new to this discussion, but all that you
        just told me has already been discussed in much detail on
        Robert's forum and my own. I had a written debate with Robert on
        this months ago showing why his argument was not valid. I
        claimed it was not valid because the conclusion did not
        irrefutably follow from the premise. You can find that debate at
        http://www.challenge2.org and go to current debates and click on
        the McDonald-Baty Debate on the age of the earth.

        I have agreed a number of times that the argument is in the
        correct format, and Robert knows this. He knew this when he
        wrote you. However, he didn't tell you this because he didn't
        want you to know what was really taking place on both forums. I
        was not trying to bother you, but he contacted you and named me
        as someone who was trying to misuse your work. I wanted you to
        know that I was not trying to misuse your work, nor was I
        misreading it. I have been studying out of Copi's Introduction
        to Logic since 1980 (fifth edition) and have a very high respect
        for it. I don't think that Robert even knew what it was until he
        and I started quoting from it. I can understand why you don't
        want to get drawn into a long and drawn out discussion on this,
        and I am truly sorry that you did, but the fact is your book says
        that if the premises are true the conclusion MUST be true in
        order for the argument to be valid. That is what I was going by.
        I am sorry that you got caught up
        in this, and I am sorry that Robert dropped my name to you as
        someone who was misusing your work. But the fact remains that as
        long as Robert's conclusion does not logically and irrefutably
        follow from the premises, his argument is not valid.

        My argument on the Constitutent Elements is an argument that
        Robert says is invalid and even says he doesn't understand it.
        However, it is axiomatic. If all the parts of my proposition are
        factual, then my proposition is true. It is valid and if I can
        prove my minor premise, then my argument is true, thus it is a
        sound argument.

        Robert cannot make that claim for his Goliath of GRAS argument.

        1. Baty admits, in the debate, that the Bible does teach that
        everything was created a few thousand years ago in six literal 24
        hour days.

        2. Baty admits that the Bible is the inspired and inerrant word
        of God.

        3. Therefore, if something has been found to be, say 3 billion
        years old, then either the dating process is wrong, or the Bible
        is wrong; not the interpretation of the Bible. That is where
        Baty's argument becomes invalid.

        He will not say that the Bible is wrong, but he will say that
        there are things that are billions of years old, so he says that
        some people's interpretation of the Bible is wrong. The Bible is
        very plain in its teaching on how many literal days it took to
        create everything (Exo. 20:9-11; Mt. 19:4-6: Mk. 10:6).
        Therefore, either the Bible is wrong, or the dating results are
        wrong. He wants to hang on to the Bible and join hands with
        atheistic evolutionists at the same time; and it can't be done.

        In Christ Jesus
        Jerry D. McDonald

        ================================================================

        --- Carl Cohen wrote:

        Mr McDonald --

        One more comment, and this will be my last.

        An argument is valid when, if its premises are true, its
        conclusion must be true.

        Given those premises, the conclusion follows irrefutably, in any
        valid argument.

        Of course the fact that an argument is valid does not assure one
        that the conclusion is true, because the premises may be false,
        even if the argument is valid.

        An argument is valid if it has a valid argument FORM -- that's
        what validity is, a formal concept.

        To say that an argument is valid in form IS to say that, IF its
        premises are true, its conclusion follows indubitably and
        irrefutably.

        Modus ponens is one of a great many valid argument forms.
        The argument Mr. Baty presented to me is in modus ponens form,
        and therefore must be valid.

        If you wish to contend that the conclusion of his argument is
        false (which of course it may be) you must contend that at least
        one of the premises of that argument are false. If both premises
        are true, then the argument (in modus ponens form) does establish
        the truth of the conclusion.

        Got it?

        Please study Introduction to Logic more carefully.

        Be well.
        Carl Cohen

        ================================================================

        --- Jerry McDonald wrote:

        Dr. Cohen,
        Thank you for clarifying this for me. It is as much as I have
        already said. I informed Mr. Baty that his argument was in a
        valid format, but his argument is not valid in the sense that the
        conclusion does not necessarily follow from the premise. I fully
        understand what you are saying about the form, but it is one
        thing to say that an argument is in a valid form and another
        thing to say that the conclusion of the argument irrefutably
        follows from the premise.

        Mr. Baty's argument (what he calls Goliath of GRAS) is in the
        modus ponens format, but his conclusion does not necessarily
        follow from the premise. This is what I have been trying to get
        him to see for the last several months and I have been taking
        what I have argued for from your book on Introduction to Logic,
        the relationship between truth and validity.

        There is no question that the argument is in valid form, which
        what I have already stated. However, just because it is in a
        valid format this will not guarentee that the argument is
        logically valid because the conclusion does not necessarily
        follow from the premise. There is no relationship between the
        truth of his conclusion and the truth of the premise. That being
        the case, as your book has stated "the argument is invalid." Mr.
        Baty wants to take one part of what you have said and make it
        sound as if his argument is a valid argument. He wrote me asking
        me if I thought his argument was valid and I told him that I
        didn't because the conclusion did not logically follow from the
        premises.

        Thank you for your cooperation
        Jerry McDonald

        ================================================================

        --- Carl Cohen wrote:

        2 January 2008

        Dear Jerry McDonald –

        Thank you for writing. I reply to your questions:

        What we call "modus ponens" is an argument form, a valid,
        elementary, argument form. Arguments – actual arguments in
        English or German or any language – may, or may not, have that
        form. Since modus ponens is an absolutely valid argument form,
        any argument that really does have that form must also be valid.

        So the answer to your question is Yes.
        You ask: "Just because an argument is in a modus ponens format
        [which is: "if p then q, p, therefore q] does this make the
        argument valid? The answer is, yes, it does, absolutely.

        You give the example: "If the cow jumped over the moon then the
        moon is made of cream cheese. The cow jumped over the moon.
        Therefore the moon is made of cream cheese" Is this argument
        valid? Yes, absolutely it is. But why should this trouble you?
        It does not follow from the fact that this argument is valid that
        the moon really is made of cream cheese. All that we are saying
        is that

        IF it is true that

        If the cow jumped over the moon the moon is made or cream cheese,

        And IF it is true that

        The cow did jump over the moon,

        THEN

        the moon is made of cream cheese.

        But of course it is absurd to assert that if the cow jumped over
        the moon the moon is made of cream cheese, (that premise is
        wildly false)

        And it is equally absurd to contend that the cow did jump over
        the moon (that premise also is wildly false.)
        Therefore the argument you give as an example supports the truth
        of the conclusion – that the moon is made of cream cheese – ONLY
        if we could know two things which are in fact totally absurd and
        false. No problem here. Your sample argument is VALID – which
        is to say that IF its premises are true its conclusion must be
        true. That does not make its conclusion true, of course.

        Read, in that same edition of Introduction to Logic, the passages
        in the very early chapters about the relations between truth and
        validity. A valid argument is one in which the conclusion is
        related to the premises in a specified way. Whether the
        conclusion of a valid argument is true is an entirely different
        matter.

        I hope this is helpful. I send a copy of this note to Mr. Baty.

        Be well.

        Carl

        ================================================================

        --- Jerry McDonald wrote:

        Dr. Cohen, I would like to ask you a question.

        On page 46 of the 11th edition of Introduction to Logic the
        following is written:

        "As noted earlier, a successful deductive argument is valid.
        Validity refers to a relation between propositions--between the
        set of propositions that serve as the premisses of a deductive
        argument, and the one propositions that serves as the conclusion
        of the argument. If the latters follows with logical necessity
        from the former, we say that the argument is valid. Since
        logical necessity is never achieved by iinductive arguments,
        validity never applies to them. Nor can validity ever apply to
        any single proposition by itself, since the needed relation
        cannot possibly be found within any one proposition."

        Also on page 43 it is written:

        "When an argument makes the claim that its premisses (if true)
        provide irrefutable gounds for the truth of its conclusion, that
        claim will either be correct or not correct. If it is correct,
        that argument is VALID. If it is not correct (that is, if the
        premisses when true fail to establish the conclusion
        irrefutably), that argument is INVALID.

        For logicians, therefore, the term validity is applicable only
        to deductive arguments. To say that a deductive argument is
        valid is to say that it is no possible for its conclusion to be
        false if its premisses are true. Thus we defind 'validity' as
        follows: A DEDUCTIVE ARGUMENT IS VALID WHEN, IF ITS PREMISSES
        ARE TRUE, ITS CONCLUSION MUST BE TRUE."

        Now my question is "Just because an argument is in a modus
        ponens format 'if p, then q,' does this make the argument valid?"
        If I say:

        Major Premise: If the cow jumped over the moon, then the moon
        is made of cream cheese.
        Minor Premise: The cow jumped over the moon.
        Conclusion: Therefore the moon is made of cream cheese.

        Is that a valid argument just because if is in the format of
        "if p, then q"? Are you saying that the argument is a valid
        argument or that it is simply in a valid form? I can put
        anything into a valid form, but would that make the argument
        itself valid?

        Major Premise: If I am a white man, then I am a black man.
        Minor Premise: I am a white man.
        Conclusion: Therefore I am a black man.

        Is the argument valid, or just in a valid "if p, then q" form?

        My reason for asking this is because I have been in a long time
        running written discussion with three men; Robert Baty, Rick
        Hartzog and Todd Greene over this. Baty has an argument which
        states:

        Major Premise: If God's word (the text) says everything began
        over a period of six days, is interpreted by some to mean it was
        six 24-hour days occurring a few thousand years ago, and there is
        empirical evidence that some thing is actually much older than a
        few thousand years. The interpretation of the text by some is
        wrong.

        Minor Premise: God's word (the text) says everything began over
        a period of six days, is interpreted by some to mean it was six
        24-hour days occurring a few thousand years ago, and there is
        empirical evidence that some thing is actually much older than a
        few thousand years.

        Conclusion: Therefore the interpretation of the text by some
        is wrong."

        Mr. Baty wrote you and responded with the following:

        "IF it is true that the proposition 'p' just above
        entails the proposition 'q' just above, [p > q]
        AND if it is true that 'p', [p]
        then 'q' is most certainly true. [q]

        The truth of the conclusion [q] is here established only if
        we know the hypothetical proposition [p > q] to be a true
        premise,
        and know also that the antecedent within the hypothetical [p]
        to be a true premise.

        ~Modus ponens~ tells us absolutely nothing about the truth of
        these premises; it is a valid argument FORM. It states only
        that
        IF p > q, AND p, THEN q."

        I understand you to say that the argument is in a valid FORM
        (something I have never denied), but to say it is in a valid form
        does not mean that the argument is a valid argument. If so, then
        why does the conclusion have to irrefutably follow from the
        premises as you state on pages 43,46 of your book Introduction to
        Logic?

        I would like for you to respond to this email. I realize that
        this gets you caught up in a discussion (that has gone on for
        several months now) even though you have little time for it, but
        I feel that Mr. Baty, Mr. Hartzog and Mr. Greene (if you have
        heard from Hartzog and/or Greene) have not given you all the
        information you needed to answer the question.

        If I can be of assistance to you in any further way to clarify
        the position on this please let me know.

        Respectfully,
        Jerry D. McDonald
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