geeez, this professor sounds like a total asshole. So there's no information whatsoever on which book this came from?
i'm trying to figure it out..... but here's something i found.
http://www.jwrider.com/lib/logicnotation.htm
turns out that the symbol i thought mean "subset" turns out to mean imply...... aahhhh...things may not look so bleak after all.....