The sinister stairs of senility

Look at these stairs leading into our basement. Do you see something unusual. Check out the bottom step. Now do you see something odd? Well, neither do I but there is a strange power emanating from that bottom step. It can't be seen or felt but it does, nevertheless, have a powerful influence on one's mind. When I go down these stairs to get something from the basement I am on a very clear mission. When I take that last step there is a sudden clouding of memory. By the time my foot reaches the basement floor I have entirely forgotten what I came downstairs to get.

Fortunately, there is sometimes a reverse effect. If I go back upstairs the fog lifts and I once more have clear in my mind what I need to get from the basement. Now it is necessary to make a fast trip to the basement past that last step or my mind will cloud over again.

Perhaps this is some kind of evolutionary thing. As humans moved beyond their cave-dwelling days life became easier and there became a need for purposeless exercise, meaning exercise for the sake of exercise rather than chasing down food. Maybe our brains evolved to make us perform physical actions over and over. I know I get lots of exercise by making extra trips to the basement when I forget what my mission was supposed to be.