A good route is a puzzle you solve with your mind and body; I'm not sure it's all that different, except for not having an advisor.

N.B. Never aspired to an advanced degree, but I know a lot of people with them.

> Because it's the complete opposite of being a PhD student I'd imagine.

I'd rather guess the following relationship: IQ is positively correlated with "openness to experience" in the five-factor model: https://en.wikipedia.org/wiki/Big_Five_personality_traits

Concerning this particular trait: https://en.wikipedia.org/wiki/Big_Five_personality_traits#Op...

"Open [to expererience] people can be perceived as unpredictable or lacking focus, and more likely to engage in risky behaviour or drug-taking. Moreover, individuals with high openness are said to pursue self-actualisation specifically by seeking out intense, euphoric experiences."