A mind like a gun

He took a book down from the shelf, saying as he did so, "A mind, like a gun, must be kept well oiled." He had never held a gun; was not quite sure where the oil went, or what might happen if it was neglected. He had looked at pictures, and imagined what gun oil might smell like. He realised one Christmas that he was imagining the smell of his auntie's sewing machine oil, and had to change it to something more like diesel. None of that mattered, since he wouldn't read the book either.