Highly intelligent and intellectual people.
I am a fairly average person. Over the years I have experienced interaction with two types of people. My interaction with highly intelligent and with intellectual people had the following in common:
1. None of them proclaimed themselves to be intelligent or intellectual.
2. They can talk about a range of subject matter but do not talk about themselves much.
I have also met with a number of people proclaiming themselves to be intelligent or intellectually advanced. They had the following in common:
1. They like to talk about themselves.
2. They don't know much and are not able to talk about any specific subject matter in any depth. They have attitude but little else.
In summary, they were, in general, not above average. Actually a bit below.