Most of you blokes will have learnt this from life experience. I've met a few birds who accept it as well but most are pretty deluded. Still an amusing read though...
http://www.laddertheory.com/just some mcsamples of the theory..
http://www.laddertheory.com/images/mansladder1.jpghttp://www.laddertheory.com/images/womansladder1.jpg"Scenario 1: Tom meets Jane. She's pretty and seems interesting to talk to. Tom and Jane start haging out and talking more and more. Tom develops an attraction to Jane, and one day tries to kiss her. Jane tell Tom she doesn't think of him that way and she wants to remain friends. The next few weeks contact between the two falls off. Jane starts fucking an outlaw biker.
Ladder Theory Explanation: Tom met Jane. Tom was immediately placed on the friends ladder. Tom didn't know this. Tom tried to jump ladders. Jane kicked Tom in the head rather than let him on and sent him hurtling to the Abyss below. The oulaw biker was not on her friends ladder (they never are) but rather on her good ladder."