QUORA today had a query on the subject: 10 unusual signs indicating high intelligence - explained by the hunter-gatherer hypothesis You can read the entire exposition, but let me just indicate the 10 plus 1 such signs  You are ( with my responses ): Messy:  maybe not totally, but my kitchen table can be improved and I never make my bed. Thin:  I was on the high side of normal most of my professional career, but was skinny until the age of 35 or so, and seem now to be heading back in that direction. Night owl:  I'm relatively normal on this one, but now and then get up in the middle of the night to do something on my computer Distrust authority:  I tend to rely on authority. Worry a lot:  yes, I do. Non-conformist:  that's me. Funny:  I like to think so Doubt yourself:  all the time. Didn't have sex until after high school:  yup. Need a lot of alone time:  I was around people all my life until my wife died a little more than a decade...