My Grandfather instructed me to always open a door for members of the opposite sex. "Why?" Was my curious response. He then explained that one day a man entered his cave like he did every day, but on this day a rock fell and hit him on the head while entering the cave. Since then he always let the woman go first. Thus began the notion that man was curtious to the opposite sex. The woman never caught on because rocks did not fall all the time. When they did. The rocks usually killed them. If not the man helped the woman recover from her injuries. This also led the woman to stay in the cave after recovery and gave the notion that man was a caregiver. Since not enough rocks were falling and the man wanted a woman to stay and share the cave with the man. Man came up with the idea of sneaking up behind woman and knocking her out with rocks. Then later because the clubs were more effective and less likely to kill the woman. Clubs were used more and more. The man always told the woman during recovery, "You are lucky you should have seen the size of the rock that hit you." Later on the woman began to suspect something was up with the man and started calling him a caveman. Not because he lived in a cave but what happened to her skull after he hit her
Opening the car door for a woman came later when the man needed to test the car brake.