Bad Ideas, Belief, Intellectual Honesty, Liars Lies and Lying, Logic, Politicians and Scoundrels, Science, Skeptical Thinking, Thinking

Lying With Logic

(About a 2 minute read)

It is a curious fact that an argument can be perfectly logical and yet its conclusion can be a lie.

To illustrate with as simple an example as possible:

All men are dolphins
Socrates is a man
Therefore Socrates is a dolphin

Any logician will tell you, the argument is logically valid.  That is, if the premises are true, then the conclusion must be true.  But of course, the premises are not true, the conclusion is a lie.  And in this case, that is quite obvious.

But perhaps there is something about us humans that causes us to be all-too-persuaded by merely logical arguments, because unscrupulous people use such arguments to dupe us all the time.

“Liberals care about touchy-feely things like hungry children and animal rights, therefore they make their decisions on the basis of their emotions, rather than according to reason.”

How often have you heard that one?  I would guess pretty often if you’ve listened to the likes of Rush Limbaugh, who popularized it.  But have you ever seen any science in support of the notion that liberals make decisions on the basis of their emotions more often than anyone else?

Of course not, and the likelihood they do seems to me quite possibly close to zero. The argument is simply unsupported by empirical evidence.  Although it does appear to offer some empirical evidence when it mentions liberal’s emotional reactions to hungry children and animal rights, those offerings turn out to be empirically untested assumptions — along with the further even more important assumption that liberals are more emotional than conservatives.

“Conservatives must have small penises because they need guns and large pickup trucks to compensate for not having large penises.”  Again, an argument that is logical, but a lie, for where is the science — where are the empirically established facts — to back it up?

From these examples we may see that the key thing to ask about any merely logical argument is — not only, “Does it make logical sense” — but, “Where are the observable facts to back it up?” Only in that way can you prevent yourself from being bamboozled by unscrupulous people.

Put differently, we should take our clue from the sciences, for the sciences do not accept as sound any hypothesis that is supported by logic alone, but demand that all hypotheses be supported by well established empirical evidence.

That is why they are the single most powerful means of discovering truths that humanity has yet invented.

9 thoughts on “Lying With Logic”

  1. It is easy to fix an argument’s validity if it is not already valid. The premises are more important. Perhaps the only reason we construct valid arguments is to rationalize questionable premises.


    1. That ties in very well with the notion that we are at our best when we arrive at tentative conclusions through intuition, and then rigorously check them against logic and empirical fact.


  2. As a very, very Bad Old Woman, I can submit one person’s observations that conservatives do tend to have rather small penises.

    The term “three and a half inch floppy” was used in a past girl talk conversation. Granted this is a single observer reporting. Just saying.


    1. Although I cannot accept your findings as likely to be universally true, the mere thought of Rush Limbaugh and Sean Hannity as possibly having peanuts for peckers sends shivers of pure delight through my entire body. Thank you so much, Sledpress!

      Liked by 1 person

      1. I will admit to one diminutive fellow who was anything but diminutive privately, now to be found occasionally whoring for Newsmax and other right wingnut channels as a talking head. But who also declared late in life that he was a trans woman and started leading a closet trans life in support groups without ever doing anything medically or publicly. Wouldn’t wash with his conservative patrons, I’m sure, which is why I still call him he, since he claims to be a woman but is really just a pussy. I cut off even cordial-ex type correspondence after he vented e-mail abuse on me for being a “liberal” and calling Rush Limbaugh and co. the “real alternative media,” which he always seemed way too smart (a literal perfect score on both SATs back when we were in high school) to believe.

        These guys are complicated. I don’t know how I ended up in a position to observe. Excessive curiosity, probably.


      2. Fascinating. It pretty much jives with my own much more limited experience of virulent conservatives these days, Sledpress. For instance, there was a locally prominent right wing columnist here in the Springs who wrote a column one day calling for the criminalization of all porn. Crazy idea. Very same week, I run into a mutual friend. Me, casually: “What do you think of Jim’s latest/”

        Him: “I was surprised! Hie and I get together every Tuesday to watch porn videos. He’s got what must be the largest collection of pregnant women porn in Colorado.”

        I’m under the impression such contradictions and hypocrisies are all too often the case with conservatives — especially virulent ones.

        And that’s even true of the smarter ones.


  3. I think you mean take our cue, not take our clue, although there is a reasonably close connection i suppose! 😉

    The problem there though is: if you only use ‘well-established’ (according to whom?) empirical evidences as the basis for any hypothesis you ‘lose’ a myriad of potentially very valuable hypotheses to test.

    You can’t find what is not known by only considering what is known. Further often what we think we know to be true often later turns out not to be. Humans are quite fallible creatures – even those who have faith in science alone. 🙂

    Just an alternate viewpoint. 😉


    1. “Cue”? No, I very much intended the word I used, “clue”. I did not want to suggest, as “cue” would have, that the scientific method of inquiry be followed to the letter, but rather that we learn from science to test logical arguments against empirical fact.

      I really don’t recognize as either legitimate or even demonstrably true any “very valuable hypothesis” that cannot stand up to being tested against empirical fact. But of course, you’re free to believe what you want to believe, and I am certainly not in the business of trying to convince people to adopt my own beliefs — no one is paying me enough to do such a thing.

      Liked by 1 person

  4. Clue taken 😉

    I was not saying though that any very valuable hypotheses should not be able to stand in agreement with established empirical evidence. Of course hypotheses need to be tested ( against something more than any form of ‘logic’ ) before they can be accepted as valid or they remain nothing but a theorised conjecture.

    What i meant was that we do not have to have as initial conditions for our hypothesis only that which has been proven to be ‘true’ (or reasonably so) – which i realise is probably not what you implied in your post. We can make wild illogical guesses as our hypothesis and see how it stacks up in our ‘real’ world(s) keeping those that ‘work’ (ie. fit in line with evidence of what is known) and rejecting those that don’t.

    You deserve to be paid more 😉


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