Nick Hornby said this quote

The difference between sex with David and sex with Stephen is like the difference between science and art. With Stephen it's all empathy and imagination and exploration and the shock of the new, and the outcome is... uncertain, if you know what I mean. I'm engaged by it, but I', mot necessarily sure what its all about. David, on the other hand, presses this button, then that one, and bingo! It's like operating a lift - just as romantic, but actually just as useful.