Wilson, Benjamin, 1721–88, English portrait painter and electrician who opposed Benjamin Franklin's theory of positive and negative electricity. Instead, Wilson supported Newton's gravitational-optical ether, which he supposed to differ in density around bodies in accordance with their degrees of electrification. Wilson also opposed Franklin's theory of lightning rods, holding that blunt conductors performed better than pointed ones. His best experimental work was on the electrical properties of the tourmaline. He was elected fellow of the Royal Society in 1751 and received its gold medal in 1760 for his electrical experiments.