I created this graphic as an attempt to illustrate possible ways to think of pleasure and pain as varying levels on a slider. This may need to be changed, and please let me know if there might be other ways to illustrate, or further questions.
Also, the following points:
1. When pain is removed it produces an experience of relief which is felt to be a kind of pleasure.
2. Even when one part of the body is in pain, pleasure can be felt in another part of the body.
3. At times mental pleasures can feel stronger than bodily pains.
4. Pleasure can only be varied (but not increased) once pain is removed.