Don't ever spend your cash on anyone elses evidence, just form your own evidence though auditioning gear and by using retrun polices, NP.
We've all been there. At some point in time I knew with absolute certainty that my ears told the truth. Then I started realising how easily all my senses could be duped, either by external inputs (e.g. no end of optical illusions) or the internal operation of the brain (think of when you've been concentrating on a task and suddenly realise someone's been talking to you for a few minutes).
It is a big chasm to leap to accept that our brains are easily capable of dramatically changing the perception of stuff that comes in through any of our sensory organs. But it's true, and none of us are capable of defeating that. Doesn't matter what we want to believe, the facts are the facts and are well-documented.
As an example, look at how TVs or professional monitors are calibrated. Never by eye. Nobody, not reviewers, professional calibrators, installers or TV/film colourists calibrate their equipment by eye. Why? Surely they are expert. Surely they have the best vision, they have seen endless screens and they know what colours should look like. Surely they and they alone are the best judge of how they want things to look. Nope. Not a single person in this field trusts their own vision, because it is well-known that human vision and colour perception is so easy to fool. We would all swear blind that a piece of grey card against a brick wall was grey, then we'd put it against a white wall and find that the card had a clear tint. So professionals test and calibrate using measurement devices.
So if professionals think that vision (our primary sense) can be fooled, why does anyone think that their ears reliably tell them the truth in anything but a controlled test? Sounds a bit suspect right? And I didn't even mention the most powerful thing, perception bias, what we want to believe. As sad as it is to say, the posters above are right. We're all experts at deluding ourselves.
The simple 'pull on your big boy pants' facts are that nobody is different, nobody is special, nobody can defeat their brains and none of us can trust our senses to be anything more than an abstracted, post-processed impression of the external world.
And setting all that aside, a really simple question (as many others have pointed out) is why recording studios don't use any of these fancy cables? Because they engineer and measure.
So as hard as it is to accept, if a dispassionate piece of equipment shows zero difference between two pieces of kit, then there is no difference. Doesn't t matter how many people say otherwise as a result of their opinion. And of course this is why all these amazing differences drop away under controlled test conditions.