I was recently arguing with a good friend of mine, who happens to believe in alien encounters, psychic powers, reincarnation etc. The argument made a cold sharp transition from a healthy discussion when I was failed to suppress a smirk when she described what an alien looked like, and ended when she eventually resorted to the relativity of truth with regards to the debate. "No!" I cried, as if contradicting someone needs the adrenaline shot of an exclamation mark. "You can't say that it's true for you that aliens visited Earth, and it's not true for me! It's either true or it isn't. There are multiple beliefs on the matter, but only one truth".
Do you really believe truth is relative? Let's say I tell everyone I can that you eat kittens. I put posters up on the streets with photos of you putting kittens in an oven, I talk on radio shows about how delicious you think kitten sausages are, and I launch a website "savethekittens.org" etc.
Now, let's say two bystanders end up debating whether it's really true that you eat kittens. One of them insists that you are innocent, but the other really believes you're guilty, and after a heated argument declares "truth is relative" and "it's true for you they don't eat kittens". Does that makes sense?
Of course not. You do not eat kittens. Truth is not relative. Belief is relative. Do not confuse truth with belief. If you do not eat kittens, you must drop the belief that truth is relative.
But now let's suppose the debate between the bystanders changes to whether kittens are cute. Once again, the argument ends with one declaring "truth is relative" and "it's true for you that kittens are cute". In this case, you have to distinguish between subjective an objective statements. Subjective statements are as much about the observer as they are about the object, while objective statements are all about the object. To go back to the previous argument, whether you eat kittens is not dependent on anyone's judgement. In comparison, a kitten's cuteness is dependent on a person's judgement. If you can't distinguish between these different types of statements, your take on reality is muddled.
That aliens visited earth is an objective statement (as are claims of reincarnation and psychic powers). It's in the same category as the statement that you eat kittens. It's not in the same category as the statement "kittens are cute". As a general rule, scientific statements are objective and impersonal, while aesthetic and ethical statements are subjective and emotional. Many statements, particularly social ones, are a complex mixture of both. Unless distinguishing between objective vs. subjective statements becomes a habit; a skill that's regularly sharpened; you're doomed to eat kittens. The cute ones too.
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