[seti0Cha]

You are assuming that you are always aware of when you might be wrong. In other words, your judgement on when a counterfactual deserves to be entertained is itself fallible, and is most likely to be wrong when you have emotional commitments around the issue that are preventing you from reasoning well. By refusing to follow a line of reasoning, you are placing yourself beyond the ability to be reasoned with.

I imagine you might dispute that that ever happens to you, and it may be that you are so thoroughly rational that it doesn't. But let me suggest a counterfactual for you: imagine you are not as rational as all that. How would you know? You would never engage in the conversations which would demonstrate this. So, as a general principle, maybe you should not assume that you are.

[dragonwriter]

> You are assuming that you are always aware of when you might be wrong.

No, I think GP is just aware that the risk of missing a useful dialogue needs to be weighed against the risk of wasting time on a fruitless one.

[TeMPOraL]

It's best to be aware of both. Yes, you may meet trolls and hardcore believers of some really stupid things, but if you always assume that anyone who disagrees with you is one of such people, you're bound to end up as one of them yourself.

EDIT:

Perhaps this is another skill, related to counterfactual analysis: being able to consider you're wrong just a tiny bit, even if you're certain you're right, just to reaffirm yourself. Holding the two conflicting states in your mind, in parallel, for however brief a moment. Kind of like speculative execution. Doesn't cost much if the other party is an obvious troll, but can pay off handsomely if you somehow ended up with a strong belief based on badly flawed assumptions.

[dragonwriter]

> but if you always assume that anyone who disagrees with you is one of such people

That’s a strawman. Not being willing to entertain every prospective interlocutor with (as in the upthread poster’s specific example) flat-earth theories is not the same as assuming everyone who disagrees with you is a hardcore believer of some really stupid thing.

[seti0Cha]

Perhaps so. However, I'm happy to let my point stand as a thing to consider when weighing those judgements. Refusing to engage in thought experiments, in my experience, is more often the product of a closed mind than a busy one.

[goodluckchuck]

Being closed minded is a justifiable defense in some circumstances. The ability to consider counter-factuals is often (and perhaps inherently) leakly. I mean, that once someone has entertained an idea, and relied on it to think about secondary and tertiary effects, they’re more likely to believe the premise… even if they have no additional information about the accuracy the initial premise. It’s an effective form of manipulation / gaslighting.

[mcqueenjordan]

Lol, it is not gaslighting/manipulation. Are you really so unable to resist the temptation to believe an idea that you must choose not to even consider it?

Proof by contradiction[1] has quite a number of important results. We shouldn't denigrate that machinery.

[1]: https://en.wikipedia.org/wiki/Proof_by_contradiction

""" G. H. Hardy described proof by contradiction as "one of a mathematician's finest weapons", saying "It is a far finer gambit than any chess gambit: a chess player may offer the sacrifice of a pawn or even a piece, but a mathematician offers the game." """

[dataflow]

Yes, thank you.