"Different or unique"......the only thing that keeps comming to mind, is that we are the same, in that we are all "different and unique" from each other. Thinking you're probably looking for a dee
per answer, and as you know, I don't do "deep".

I seem to agree with much of resserts comment.

“What makes you think you are different…”

You didn't ask why we think we're different, but rather what makes us think we're different. Was that an intentional choice of words to ask a subtly different question? If so, I'd say we have a cognitive aspect and subjective perspective that makes us naturally feel separate, but we also have mental and emotional mechanisms that make us want to fit in to some degree and be part of the group. There are social aspects, too, as in the U.S. there's a dogged individualism that isn't as prevalent in some parts of the world. But, if you are asking simply what I think sets me apart, I'd say that there's not much. Yes, we're each unique as a whole, the sum of our parts, but I don't think I'm the smartest (or dumbest) person, I don't think I'm the most (or least) introspective, I'm not the most ambitious (or laziest), etc. I might be rarer in some ways, but very mediocre in others. Does the combination of my rarer attributes make me distinct? Maybe. I honestly don't know. But I also don't think it matters. I'll be who I am, until I'm not.