1.) Someone who works in Metaphysics. AKA Metaphysician. But that is a faulty term, as a Metaphysician would obviously work in metamedicine - whatever that is. The root of metaphysics is physics and those who work in physics are physicists, thus Metaphysicist.
2.) A Moderator of the Better Living Through Chemistry (BLTC) forum totse.com
An Alchemist was just one subtype of Metaphysicist.