Too many men and women alike are afraid of the word "no". Men are afraid to hear it, and therefore avoid behaving in any manner that might cause them to hear it. Women, on the other hand, are afraid to take responsibility for saying it.Twenty-five years after I registered for college, we're still searching for an alternative to the stark simplicity of "No." And unfortunately, there's just no substitute. If you want to "teach men not to rape" -- a formulation that floated around the Internet a lot in the days after the Rolling Stone story was published -- then you need to give them a rule that can be clearly articulated, and followed even if you've had a few.That's why "no means no" worked so well, even if it wasn't perfect. It's a heuristic that even a guy who's been sucking at the end...