Do you believe in magic?
If you asked a magical wizard about these underwear, he'd probably be like, "Hey! I'm a magical wizard! Don't you have anything more important you wanna ask me about than underwear?!?"
But if you ask an underwear expert about these underwear, he'll probably say, "These underwear are magical." And that's how you know that underwear experts were the true magical wizards all along.
Also, a quick disclaimer: the underwear expert would be using the word "magical" in a non-literal sense here. These underwear don't have any actual magic powers. That we know of.