Originally Posted by
fini 
promising that4 will never be a prime number is a category mistake.
Yes fini, thank you. There is nothing to promise about 4 not being a prime.
What if there is also nothing to promise about anyone’s capacity to make an irreversible pledge to never drink/drug again? I have done it. Even if every other human brain that learns of my pledge believes it must be reversible, that doesn’t mean that it is reversible, because there’s no way anyone can prove that my pledge is reversible.
I wonder if “I promise that GT’s Big Plan is reversible.” could also be a category error?