People say that such-and-such is 'unthinkable.' An electromagnetic pulse, for example, one that destroys the power distribution grid, would be a calamity in comparison to which the COVID-19 pandemic would pale into insignificance. An EMP event is said to be 'unthinkable.' And yet we are now thinking about it. What one thinks about can be thought about, and is therefore thinkable. So the calamity in question is precisely not 'unthinkable.' Nor is it 'unimaginable.' I can imagine it and so can you. People use these expressions because they thoughtlessly repeat what they hear other people say. That's my explanation. Do you have a better one?
Not every test is a litmus test. So why do people refer to any old test as a litmus test? Same explanation. Not every record is a track record. Not every list is a laundry list. I could continue with the examples. And you hope I won't. Don't be a linguistic lemming. The mind you save may be your own.
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