Three older ladies were discussing the travails of getting
older.
One said, "Sometimes I catch myself with a jar of
mayonnaise in my hand in front of the refrigerator and can't
remember whether I need to put it away, or start making a
sandwich."
The second lady chimed in, "Yes, some times I find myself
on the landing of the stairs and can't remember whether I
was on my way up or on my way down."
The third one responded, " Well, I'm glad I don't have that
problem; knock on wood," as she rapped her knuckles on the
table, then told them "That must be the door, I'll get it!"