I’m often called an expert, and at things for which I don’t believe I am. And I see that “expertise denial” often in others (and mentioned above as well…). In almost all cases of this, it is those less knowledgeable in a subject that are calling those that are more knowledgeable to be experts… so…
Expert(ise) is a qualitative measure of the knowledge differential between two persons.
Consider two people in a room, both having considerable knowledge on a subject but one more so than the other. The less knowledgeable person is going to refer to the other as the expert on the subject.Now imagine a third person who knows very little of the subject walks into the room… they are going to view them both as experts.
Where the “knowledge differential” is negligible or relatively small, one might refer to the other as a colleague or associate. Where the differential is great, it might be “teacher/student” labels that one refers to… or a host of other labels that put magnitude on the knowledge differential…
So while I am reluctant to think of myself as an expert, I will concede to being an expert relative to some, and a novice relative to others. But I much rather prefer to view it as:
"I can learn from many others, and share learnings with many more"