[AlexandrB]

> A free will is a healthy will, in the sense that our decision mechanism is not broken by e.g. drugs, electrodes or mental illness.

Isn't the drug example a contradiction? If my brain was healthy ("free") when I decided to take drugs, why would the resulting drugged state be less "free"? After all, it was my "free" choice to take the drugs and alter my mental state.

Edit: Also the definition of "mental illness" is somewhat nebulous and not historically fixed. Homosexuality was at one point called a mental illness.

[unknown_apostle]

Consider hypnotics used during light medical procedures to keep you awake but compliant. From a state of more freedom you can freely choose to enter a state of arguably less freedom. Why would this be a contradiction?

> Edit: Also the definition of "mental illness" is somewhat nebulous and not historically fixed. Homosexuality was at one point called a mental illness.

Yep, insights and definitions of illness will keep changing. But while insights in the details of e.g. psychosis may vary, few would deny a correlation with chemical issues.