“Chickens are fluffy and helpless, but they descended from true dinosaurs.”

Spock: “The engines are likely to fail if we stay in hyperspace, Captain.
Kirk: “But we need to save the planet Empiricus from the supernova!

If someone makes a statement of the form “A, but B.” what they typically mean is that A is true, and — even though A is evidence against B — B is true nonetheless. The chicken statement is of this form. This is a pretty useful bit of English.

But sometimes, it doesn’t effectively mean that. In arguments like the one on the Enterprise, if the first speaker asserts A and the second speaker responds “But B!” this can mean “What you said was irrelevant, because B.” Sometimes this is a legitimate correction, and sometimes it’s an attempt to not have to concede A.

I propose a tiny trigger-action-plan to consider using ‘and’ every time you want to use ‘but’. It’s the epistemically sound kin of improv’s “yes and” technique. You won’t want to replace ‘but’ every time, because one often wants to emphasize the surprise. But when it feels like it would hurt to say ‘and’, consider doing so. The engines are likely to fail if you stay in hyperspace, and you need to save the planet Empiricus. This is more painful to consider, and you are now ready to solve the problem. Can you reverse the polarity of the transducer? No, because that would take thirteen hours. The engines will soon fail, you cannot reverse the transducer, and you need to save the planet Empiricus. What will you do?

The universe is filled with unfortunate facts that are simultaneously true. It’s an essential skill of a rationalist to hold seemingly contradictory facts in their mind until they discover the resolution. Simplifications are instrumentally useful and can be used safely in context. But when the planet Empiricus is at stake, you must know what simplifications are okay and which are fatal. Star Trek is notorious for implausibly successful save-the-day actions; Kirk never gets his fact-denying comeuppance. Nature is notorious for indifference.

To bring it closer to Earth, consider a favored political policy, like minimum wage. Does your stance on the issue have any negative side effects? Does your opponent’s have any positive effects? Minimum wage violates the freedom of business owners — and some good people have trouble finding a job that will pay them a living wage. Are all low-income people lazy and deserving of their strife? Are all business owners greedy or biased in their wage setting? Certainly not; there are just two unfortunate facts, and we only have solutions to fix one of them. Let us remember this, so we know to keep working toward better solutions.

Like the mantra “That which can be destroyed by the truth should be”, this is a practice for your own mind. If someone avoids your true statement by responding “But B!” with another true statement, don’t tell them to say ‘and’ instead; repeat “A and B” to yourself first. See whether this loosens your beliefs.