What makes an Engineer?

What allows someone to call themselves an engineer?

I think of myself as an engineer, but how do I know I am one?

An engineering degree is neither necessary (plenty of engineers never went to college) nor sufficient.
A Profession Engineer license isn't something I have. If I'm going to consider myself as an engineer, that can't be part of the criteria.
Working in a job with the title of engineer - now we're getting warmer. Again, though, it is not necessary, and there are a fair number of examples to show it isn't sufficient either.

The mindset, then? Is it enough to think like an engineer? Closer, but I think if you think like an engineer but don't act on those thoughts, you're still missing something important. We do not (thank all the gods) live in a world with Thought Police.

Professional achievement? An engineer is someone who does engineering. A tautology, of course, but the closest to the mark we've come yet. Engineering is about creating items that are usable and useful. The problem here is that someone who has not yet created something can't be an engineer. Maybe that's OK - back when I was a paramedic, several senior medics told me that you weren't a real paramedic until you'd worked a pediatric code. So perhaps that first creation is your initiation. Every time you create something, you renew your engineeringness.

Unrelated, hi Kathy! Congratulations on the first non-anonymous comment!

Of course, since your profile is blocked, I'm still waiting for the first comment I can VERIFY comes from who I think it is coming from...