Logical consistency is a social burden

Maintaining coherent beliefs is not personally useful

From Narrow To General AI
9 min readMar 2, 2024

In a previous post on the nature of logic I mentioned in passing that logical consistency is a learned skill, and that the motives that drive its acquisition are all social. I provided an argument for this in an extended footnote, but I always felt the exposition fell short. This post will make a more thorough case for why consistency lacks any benefit for an individual outside of social interactions; and worse still, it is actively detrimental.

The necessity of symbols

Talking to people always serves a purpose. You speak to others in order to change them in some way. You may be asking them to carry out a particular action, or perhaps to change their beliefs. Of course, reality will impose restrictions on which of your requests are ultimately feasible. If you ask someone to go to the grocery store and stay home at the same time, their inability to accomplish both will be frustrating to them. The tasks may be individually achievable, yet their combination is not. That in itself does not signal an inconsistency though, since you may simply be mistaken — such as when you ask them to get an item from a store that doesn’t have it. What makes it inconsistent is that you know that doing one specifically undermines the other. Inconsistency is a “sin”, not an error, because the other person suspects you are aware, or believes you should be aware, that reality makes the actions mutual exclusive. When others speak with you, and listen in good faith, they’d like the things you say to be consistent.

This applies both to requests for action, and to assertions of fact. If you say that your wallet is in the taxi, and also that your wallet is right here, others may have difficulty deciding whether or not you need help calling the taxi company. Or if you say that your favourite movie is X, and also that it’s Y, they may be unsure of which movie to recommend for movie night, or what tie-in merchandise to buy you for your birthday. Note, your conflicting assertions are not a problem for yourself — you are free to watch either movie whenever you please. It is the inability of others to coordinate with you that causes the tension.

Human cognition is quite fluid. You may change your mind at any time, and in whatever way your whims compel you. And you rarely check to make sure your resulting beliefs are internally consistent. Inconsistencies generally become apparent to you only when you discuss your thoughts with others, or when you think about them as explicit assertions. Before you can do either, however, you must first convert your nebulous thoughts into concrete symbols like words, along with their fixed relationships of meaning. You will only be able to gauge the consistency of beliefs once you have clearly defined them. So when you stated above that X was your “favourite movie” you first solidified two things which were perhaps not so solid in your mind, namely:

  1. You compressed all of the scenes of X into one entity — a “movie” — and evaluated them altogether. Your statement overlooked the fact that you may like some scenes, or some parts of scenes (like the special effects), and not others.
  2. You treated preference as a static, fixed ranking. Your statement did not account for changes in preference based on your mood or your evolving tastes; or that you may like the acting in one movie, and the narrative of another, and both can fluctuate over time.

As is evident, before you can check for consistency, you must first constrain your free-flowing thoughts into narrow concepts and symbols.

Why would you ever press your thoughts into such a straitjacket? It’s simple: because collaboration with others would not be possible unless you convert your thoughts into symbols and their relations that other people understand. Your peers can’t keep track of the kaleidoscope of impulses that flow along in your stream of consciousness. Moreover, they can’t even understand your thoughts at all unless you express them as previously defined terms; terms like “store”, “buy”, “want”, etc. That is the primary function of language: to establish shared symbolic entities.

Compared to the wide-open landscape of personal cognition, the space of collaborative terms — which we call “language” — is quite narrow and restrictive. You’ve no doubt experienced moments when you can’t find the right words to express your needs to others. In those moments you are realizing the vast gap between personal thoughts and publicly shared symbols. Consistency, however, is a feature of the symbols; you can’t define consistency unless you can concretize what exactly it is that will be judged as “consistent”. The discussion of your favourite movie broke down when we dissolved the concept of “movie” into its sub-elements. Only by reestablishing new terms and their relations can we resume the investigation into its consistency. This, of course, will once again constrain the space of meaning.

The benefits of avoiding logic

Logical thinking is a subset of all thinking, and a refined one. This should not be taken to mean that non-logical thoughts and beliefs are inferior to their distinguished cousins. There are benefits to keeping the mind flexible, as in logically inconsistent. For instance, you never really know that the terms and relations you have fixated upon are the best ones by which to frame your thoughts. Keeping an open mind to new ways of thinking, new concepts, and new paradigms is necessary for human ingenuity; even though such thinking may seem irrational in light of the previous set of expectations. For example, you may spend much of your life reasoning about how to avoid death; yet once you realize that you must die eventually, you may accept and even begin to embrace death. The latter would be illogical according to the previous schema. A change of values also changes the conditions of what is reasonable.

A second reason to avoid logical formalization is that you can’t always clearly structure your thoughts in terms of logical predicates, and describe why your beliefs are the way they are. For example, you may find that you deeply mistrust a person you just met, yet not be able to explain the cause. Much of everyday decision-making is driven by gut feelings, habits, and intuition based on past experiences.

Such informal thinking is necessary, since the world rarely provides clear-cut answers to your questions. Often you must make decisions on scant information; one or two examples at most. Your resulting beliefs will be driven by spurious associations and flawed deductions. You may mistrust an acquaintance merely because he is similar to someone you had a conflict with before. And you don’t always have the time or opportunity to thoroughly double-check your beliefs and the reasons behind them.

In many such cases, a belief that appears logically inconsistent could actually be justified, because there might be a hidden, unexpressed factor that makes it valid. In the example above, where you mistrusted a person based on their similarity to another disreputable person, perhaps you detected a hint of conniving double-speak in both of them. Or perhaps they both had a moustache. You may not realize which it is that influenced you, and are often unable to discover the deeper connection.

This could show up as an apparent inconsistency to others. Say that before you met this person, you had announced your hope to engage in a profitable business deal with his company. If you now reject him due to an indescribable gut feeling, you would, on the surface, appear to be acting inconsistently with your earlier claim, and for seemingly no reason. Others around you will have to change their plans, and your behaviour will appear unreliable. You can still cancel the deal if you want to, but you will have difficulty convincing your partners that it was the right choice. Acting consistently here, as always, would be done for the sake of appearance.

We are never more true to ourselves than when we are inconsistent. — Oscar Wilde

On the other hand, if you ignore your gut feeling in an attempt to appear consistent — even if only to yourself — you may end up causing yourself a lot of harm. Just because you couldn’t figure out why you mistrusted someone doesn’t mean there wasn’t a reason. Many gut feelings are well-founded. Moreover, formalizing your thoughts in a way that can be checked for consistency requires extra effort and introspective skills that some people simply don’t possess. This places an undue expectation on someone who could otherwise make good decisions to have to clearly explain them. Not only that, but your explanations may simply be rationalizations, which are designed to convince others and yourself, and don’t reflect the true reasons behind your actions.

In any case, by the time you uncover and formalize the terms of your argument, the facts may have changed. Formal logic is always behind the curve compared to common sense, and must play catch up. Maintaining logical consistency is far too languid as a philosophy for everyday life; it is restrictive when you need to be flexible, stringent when it is advantageous to fly by the seat of your pants. The forces of reality will always push your thinking one way or another, and your explicit reasoning is a delayed echo of these fundamental drivers.

I’ll admit that following your gut often results in irrational judgments and produces unfounded conclusions. Much needless suffering may be laid at the feet of poorly thought-out decisions. On the whole though, gut feelings get a bad rap. We only label gut feelings as “irrational” after they cause us problems. The rest of the time we either overlook them, or praise them with such panegyrics as “prescience”, “intuition”, and “professional experience”. And for good reason: most of life is a-rational, as in it is neither irrational, nor rational. Logic is only useful in a closed system of near-perfect information. Outside this, it feels calcified, petrified. Its application to life’s problems causes stagnation that is comparable to the progress of Münchmeyer disease in a healthy body.

Where’s the value?

Maintaining logical consistency takes effort. It is not automatic. So you better have a good reason for taking the time to do it. Alternatively, you could go about your day comfortably holding mutually contradictory beliefs. Even when you become aware of this compromising situation, you may often decide to leave things as you found them. “Sure”, you may think one day, “God is all-powerful and all-good, and yes, evil exists, but perhaps God works in mysterious ways that I just don’t understand”. It’s not always obvious what the logically consistent path is, and you can only fix your thoughts if you know what “fixed” looks like.

Have you ever found yourself going back to a relationship that drives you mad? Or spending money on video games you don’t even play? Other people may judge you for your inconsistency, but their insistence that you act consistently is a sort of cognitive Puritanism, a judgmental intrusion into your thinking. They are like the ascetic monks of logic, fighting against their true needs, and reaching for an impossible cleanliness of mind. They may not understand that the joy of buying games is in the anticipation, and not in playing them. They may not realize that the secret validation of romantic love is life-affirming. And you yourself may not realize these either; you simply act on your gut. Your body knows what it wants and will maintain its own internal coherence based on its needs, such as when you avoid touching a fire once you’ve been burned. Whether or not your intellect follows suit is a matter of social self-justification.

So why be consistent? What personal benefit does consistency bring, except to justify your thinking directly to others, or in imagined conversation with them? Perhaps, if the day came when you believed you have achieved perfect cognitive consistency, you would sleep better at night, in the same way a person innocent of crimes would sleep with an easy conscience. This seems understandable. Yet just as the concept of a “crime” doesn’t make sense without the existence of other people against whom the crimes are committed, sins of inconsistency are only meaningful where other people are holding you to some standard. And as with the pangs of a guilty conscience, you’ve internalized their standards as a personal ethical principle. Consistency is a kind of burden society places on you, one which most humans feel free to shake off as soon as it is convenient to do so.

Post script: There is an objection to this argument that is so common it is worth addressing in a footnote. Surely mathematical consistency is useful even when you are alone, outside society? I would differentiate here between mathematical inference (e.g. 1 + 2 => 3) and mathematical consistency. The latter means you strive to ensure you get the same result every time. If on two different occasions you ended up with two different numbers of, say, apples, there is no benefit to you in looking backwards to find a consistent value. You would merely adopt the most recent number, as it was possible some apples had been lost or gained in the interim.



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