Good points flying.
Most humans intuitively know that love isn't caused by chemicals released by the brain. These chemicals are correlated but are not causitive.
I would illustrate it like this. Suppose a skeptic remains unconvinced that the images appearing on a television set are coming from somewhere else. He believes they are due to the internal material components of the television set only. He messes with some parts and the images become fuzzy which strengthens his belief that they are only due to the physical components in the set. He moves another peice and a line begins to run thru the image. He cuts a peice out and all images stop. Because of his experimentation he now is completely convinced that the images that appear on the television screen were due solely to the material components and nothing else is necessary for them. As we know he only has part of the picture. Those images were streaming in from some other place but the physical components were correlated but did not create the images.