From a letter from Benjamin Franklin to Samuel Mather, May 12, 1784:

You mention your being in your seventy-eighth year; I am in my seventy-ninth; we are grown old together. It is now more than sixty years since I left Boston, but I remember well both your father and grandfather, having heard them both in the pulpit and seen them in their houses. The last time I saw your father [Cotton Mather] was in the beginning of 1724, when I visited him after my first trip to Pennsylvania. He received me in his library, and on my taking leave showed me a shorter way out of the house through a narrow passage, which was crossed by a beam overhead. We were still talking as I withdrew, he accompanying me behind, and I turning partly towards him, when he said hastily, ‘Stoop, stoop!’ I did not understand him, till I felt my head hit against the beam. He was a man that never missed any occasion of giving instruction, and upon this he said to me, ‘You are young, and have the world before you; STOOP as you go through it, and you will miss many hard thumps.’ This advice, thus beat into my head, has frequently been of use to me; and I often think of it, when I see pride mortified, and misfortunes brought upon people by their carrying their heads too high.

B. Franklin.