Well, you’re right that in the mental illness case my definition works badly, but I can’t think about a better precise definition right now (can you?); probably something like selecting a specific “sub-process” in brain which is related to the conscious experience, but it’s fuzzy and I’m not even sure that such separation is possible.
I think the correct intuitive definition of “locus of control” is “those things you can do if you want to”.
I have a feeling that it is a rephrasing of “things under your control”.
Causality is entirely about hypothetical interventions; to say “your way of thinking affects your IQ” is just to say that if I was to change your way of thinking, I could change your IQ.
Actually, I’m arguing that causal arrows are pointing in the opposite direction: if I was to change your IQ, I could change your way of thinking. The rest of article is about what happens if we assume IQ fixed (that somehow resembles Bayesian inference).
I was kinda surprised to see IQ as an external factor; my impression is that internal vs. external locus of control is actually personality traits vs. circumstances and environment, and IQ obviously falls into the first category.
If you consider IQ and mental health external factors, what are the internal factors, then? Willpower? But willpower is determined by the brain structure just as IQ and mental health and other personality traits.
Basically, if you assign everything to the “external” category, so that the “internal” is an empty set (or almost empty), then one’s success is determined by “external” factors. No surprise here.