I read about E-prime in my late teens, and while I don't actually use it in everyday language, thinking about the implications has deeply changed the way I think about things.<p>The basic idea for me is that all instances of 'is' are technically false statements[0]. "That chair is red" is false, not just in the boring sense that the chair probably has some non-red bits, but more fundamentally in the sense that redness is a result of you looking at it, not an intrinsic quality of the chair.<p>The E-prime version of that would be, "That chair looks red to me." A pedantic and unimportant difference in that example, but consider the difference between 'Bob is dishonest' and 'Bob lied to me.' The latter may or may not be true, but it is clearly a subjective observation and can be argued with on those terms. The former phrasing, taken literally, implies the existence of a hypothetical quality called 'honesty' and asserts that Bob doesn't have it, which is both literally false (because there is no such quality, at least not that we can measure) and less useful (because we assume the speaker has some reason to think Bob is dishonest, but don't know what it is).<p>The point is that it's a bug of our language (inherited from Aristotle, according to Korzybski) that we commonly phrase opinions as if they were facts, and that we describe things by assigning them imaginary intrinsic qualities and then talking about them as if they were observable. Once this meme infects you, you see it everywhere. The chair 'is' red, Bob 'is' dishonest, [politician] 'is' crazy, a photon 'is' a wave. In every case, rephrasing those in e-prime would be clearer and more accurate.<p>Some might still say this is just semantic nitpicking. In some contexts, sure. But I've found it to be very helpful, mostly in sciences but also in philosophy, art, and life generally. And it is particularly relevant to internet arguing. Not in the sense that you get to say, "Hah, you used 'is' so you're wrong!" but in the sense that you can more easily see when someone has said something you disagree with, but can't argue against because it is not arguable. Consider e.g. "vim is better than emacs". There's no point in debating that until you find out why they think that. That may seem obvious in the abstract, but in practice I find that most people would rather just guess, as in "I'll bet he means X, so I will now write 8 paragraphs angrily explaining why that's not true..." than ask.<p>0: "You just said is!" I hear you cry. Okay you got me. More precisely, it's all instances of the 'is of identity', as distinct from uses like "That <i>is</i> what I said" or "What <i>is</i> your drink preference." What E-prime tries to avoid is not specific words, it's phrasing a subjective statement about an observation in the form of an objective statement about an intrinsic quality of a thing.