One is never ill in general. One is always ill in relation to some activity. It is not cancer that makes me ill. It is because I cannot work, or run, or swallow that I am ill with cancer. The loss of function, the obstruction of activity, cannot in itself destroy my health.
I am too heavy to fly by flapping my wings, but I do not complain of being sick with weight. But if I desired to be a model, jockey, or dancer, I would consider excess weight a disease I would like to be cured of.
Carse, Finite and Infinite Games, 3.56