According to I-zheet M'drurz :
Are you trolling, or are you serious???

There are industry standard color codes for wires. Green is
Ground. White is Neutral. Are you seriously suggesting that
a manufacturer would code a wire that should be black as a
white colored wire?

Neither wire on a switch is neutral. Virtually every switch ever
installed has one white wire on it. You don't even have to mark it
in this particular instance, because the NEC assumes everyone _knows_
that any wire connected to a switch is potentially hot.

On a "switch circuit" circuit to a switch, one of the wires pretty well
has to be white. But they're both hot. If I remember correctly, the white
wire is supposed to be the one "always hot", and the black one is the
switched wire one going to the center pin on the lightbulb socket.

Ie: in the fixture, the fact that you have one white wire in a wirenut
with one or more other blacks is supposed to be a good hint that that
white wire is hot. Secondly, the other wire (which goes to the light
bulb) is black to indicate that it's hot.

I have seen simple dimmers with white and black wires. Makes it obvious
how to connect switch legs to the switch (even if it doesn't matter),
doesn't it?

Most dimmers I've seen are two black wires.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.