Is that like ego, or just idiocy?

So a couple of posts ago I wrote about academic reading being reading with "a higher seriousness of intent." I knew at the time I wrote the phrase that I was plagiarising it from somewhere, but I couldn't remember where and figured nobody would notice.

Well, I finally figured it out, and I was right; nobody would ever have noticed. The phrase is from the title of a paper I wrote sophomore year. I plagiarised myself. I don't know if that means my writing ego is huge (because I quite like the phrase, even now that I know I was the original writer) or that I'm just not overly creative. I think it's funny, though.