What proof do you have?
Hillary Clinton
It's the same proof you have that Christians exist.
There are people who themselves to be Christian, just like there are people who say they are witches.
wic⋅ca /ˈwɪkə/ Show Spelled Pronunciation [wik-uh] noun
witchcraft, esp. benevolent, nature-oriented practices derived from pre-Christian religions.
Origin: 197075; OE wicca (male) sorcerer (ME wicche, mod. dial. witch); see witch