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The Laws of ThoughtLESSON 3
"Liberalism is in tension withdemocracy. Democracy is a meansnot only of dispersing political powerand thus of protecting ...
An I Proposition.Some S is P, does not rule out All S is P, thecorresponding A proposition. It leaves this open.An A Propo...
“If A, then B” “If A, then not-B.” Thisdoes not violate the law of contradiction.Can you see why not?
The law of contradiction says thatsomething that exists cannot havecontradictory properties.● A hypothetical proposition d...
● “If you deny the law of contradiction, thenyou also have to affirm it”Only if someone says, “the law of contradictionis ...
Law of Identity
As far as metaphysical reality is concerned (omittinghuman actions from consideration, for the moment),there are no facts ...
● Contradictory and ContraryPropositions● An A proposition and an O propositionsare contradictories.“All men are mortal” (...
A distributed term applies to the whole extension ofthe term.An undistributed term does not.In “All men are mortal”, “men”...
Because cooking takes less time and labor than itused to, the cost of eating has dropped…This is whatI mean when I say tha...
Because cooking takes less time and labor than itused to, the cost of eating has dropped…This iswhat I mean when I say tha...
“The basic defense, [of appropriatingunowned property by claiming it] however,is quite general and straightforward. It ist...
“The basic defense, [of appropriatingunowned property by claiming it]however, is quite general andstraightforward. It is t...
How to Think: Introduction to Logic, Lecture 3 with David Gordon - Mises Academy
How to Think: Introduction to Logic, Lecture 3 with David Gordon - Mises Academy
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How to Think: Introduction to Logic, Lecture 3 with David Gordon - Mises Academy

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How to Think: Introduction to Logic, Lecture 3 with David Gordon - Mises Academy

  1. 1. The Laws of ThoughtLESSON 3
  2. 2. "Liberalism is in tension withdemocracy. Democracy is a meansnot only of dispersing political powerand thus of protecting the privatesphere against invasion by the publicsphere, but also of enabling people toenforce their dislike of other peoplesself-regarding behavior"Richard Posner, Overcoming Law, (Harvard, 1995),p.25.● This is an ignoratio elenchi. Posner saysthere are problems with democracy. Buteven if he is right, this doesn’t respond tothe point about elitist judges.● Why does Posner start talking aboutdemocracy? He assumes that withoutjudicial review, all decisions would be madeby majority rule.● Joyce calls this a “false cause” fallacy.Richard Posner responds the objection to judicialreview that it permits elitist judges to impose theirvalues on the rest of us in this way:Review
  3. 3. An I Proposition.Some S is P, does not rule out All S is P, thecorresponding A proposition. It leaves this open.An A Proposition implies the corresponding Iproposition.“All S is P” implies “Some S is P”● This isn’t true in mathematical logic.Examples:“All men are mortal” implies:“Some men are mortal”.“Some men are mortal” leaves open:“All men are mortal’● In ordinary language, we often don’t say“some” if we can say “all”.I wouldn’t say, “Some U.S. Presidents were olderthan 35” if they all are. But this is isn’t arequirement of logic.Review
  4. 4. “If A, then B” “If A, then not-B.” Thisdoes not violate the law of contradiction.Can you see why not?
  5. 5. The law of contradiction says thatsomething that exists cannot havecontradictory properties.● A hypothetical proposition doesnot say that anything exists.”● If A, then B” and “If A, then notB.” are not contradictory unlesswe assert that A exists.
  6. 6. ● “If you deny the law of contradiction, thenyou also have to affirm it”Only if someone says, “the law of contradictionis never true.” If someone says, “There is atleast one true contradiction”, this refutationdoes not work.Is This Correct?
  7. 7. Law of Identity
  8. 8. As far as metaphysical reality is concerned (omittinghuman actions from consideration, for the moment),there are no facts which happen to be but could havebeen otherwise... Since things are what they are, sinceeverything that exists possesses a specific identity,nothing in reality can occur causelessly or by chance.The nature of an entity determines what it can do and,in any given set of circumstances, dictates what it willdo." (The Ayn Rand Lexicon, 333.)Apart from human actions, however, Rand believed that everyevent was determined in the sense that, at any given moment,only one outcome was possible — nothing that happens couldhave happened otherwise. Leonard Peikoff uses the example ofa helium-filled balloon to clarify the issue: if, under the same setof circumstances, it were possible for a balloon to act in morethan one way — if it could rise or fall — then the law of identitywould be violated. "Such incompatible outcomes would have toderive from incompatible (contradictory) aspects of the entitysnature. But there are no contradictory aspects. A is A."This is a misapplication of the law of identity. If thehelium balloon goes up on one occasion and downon another, these aren’t contradictory properties atthe same time.If Peikoff says that incompatible propertieswould have to derive from incompatible aspectsof the balloon’s nature, he is assuming the lawof causation. But he is trying to show that thislaw follows from the law of identity, so he isbegging the question.
  9. 9. ● Contradictory and ContraryPropositions● An A proposition and an O propositionsare contradictories.“All men are mortal” (Universal affirmative) and “Somemen are not mortal” (Particular negative)● An E proposition and an I proposition arecontradictories.“No dogs are evil” (Universal negative) and“Some dogs are evil.” (Particular affirmative)● An A and an E proposition are contraries.“All men are mortal” and “No men are mortal”
  10. 10. A distributed term applies to the whole extension ofthe term.An undistributed term does not.In “All men are mortal”, “men” is distributed—all men.“Mortal” is undistributed. We don’t know how many ofthe mortal beings are men.
  11. 11. Because cooking takes less time and labor than itused to, the cost of eating has dropped…This is whatI mean when I say that free markets have created theobesity epidemic. Advances in food technology havereduced the monetary and time costs of eating, andthese technological advances are a result of freemarket enterprises responding to consumer demand.Some market defenders might dispute me on thismatter, pointing out that the obesity epidemic hasonly taken off in the last several decades, whereascapitalist enterprise has only been around for at leasttwo hundred years. But by this reasoning, wed beforced to conclude that free markets arentresponsible for HDTVs, or iPods, or aluminum siding,none of which existed at the dawn of time.Peter Ubel, Free Market Madness (Harvard Business Press, 2009), pp.27-28
  12. 12. Because cooking takes less time and labor than itused to, the cost of eating has dropped…This iswhat I mean when I say that free markets havecreated the obesity epidemic. Advances in foodtechnology have reduced the monetary and timecosts of eating, and these technological advancesare a result of free market enterprises respondingto consumer demand. Some market defendersmight dispute me on this matter, pointing out thatthe obesity epidemic has only taken off in the lastseveral decades, whereas capitalist enterprise hasonly been around for at least two hundred years.But by this reasoning, wed be forced to concludethat free markets arent responsible for HDTVs, oriPods, or aluminum siding, none of which existedat the dawn of time.● This is an ignoratio elenchi.● The relevant point is when the advances in foodtechnology occurred, not when free markets began.● Ubel argues that advances in technology causedthe obesity epidemic. If they didn’t, it’s irrelevantwhether free markets were responsible for theadvances in technology.
  13. 13. “The basic defense, [of appropriatingunowned property by claiming it] however,is quite general and straightforward. It isthat if a prospective owner can in factperform it, taking possession of a thing isa feasible act of his that is admissible if itis not a tort (in this case not trespass) andviolates no right; but this is the case bydefinition, by the thing being identified as‘unowned’.”Anthony de Jasay, Against Politics, Routledge, 1997,p. 173
  14. 14. “The basic defense, [of appropriatingunowned property by claiming it]however, is quite general andstraightforward. It is that if aprospective owner can in fact performit, taking possession of a thing is afeasible act of his that is admissible if itis not a tort (in this case not trespass)and violates no right; but this is thecase by definition, by the thing beingidentified as ‘unowned’ ”This begs the question: it assumesthat there are no rights to unownedproperty.

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