A former co-worker of mine is on Google+ and I've added him to one of my Circles. No problem there.
However, in the "Find and Invite" section I also see his name with the envelope icon indicating that he's not participating in Google+. I presume that he's there because he is in my Google Contacts.
How can I get Google+ to realize they're the same person?
Best Answer
I seem to have found the solution. The key was in my Google Contacts.
Apparently, because I'd added this person's Google+ profile it also created a contact under my "other" contacts. A quick search on part of his name revealed the two entries. I simply used the Google Contacts "Merge Duplicates" feature, waited a little while for everything to get in sync, et voilà! No more duplicate.
(In fact, the "Other Contacts" section is filled with people whom I have added to Circles in Google+.)