IMO no engineering degree, no engineer. There’s some exceptions for incredible self taught folks but they’re drowned out by so many others that just use the title without the skill
I think most engineers have an understanding amongst each other, regardless of their specialty, we can all teach ourselves to problem solve. So many math and physics classes as an EE just to get to my core classes. It definitely a certain type of person to get through the thick of it.
Why stop there? No PE no engineer.
You can arbitrarily gatekeep the title all you want, but the reality is that engineering is a group of concepts and ideologies that can be applied to many disciplines in many ways.
Just because the person doing the engineering doesn’t meet your personal standards doesn’t mean engineering isn’t being accomplished.
There is nothing about the engineering process that requires a degree.
All that being said. A professional engineer is an actual controlled title. (You can’t sign documents as a PE without getting the license, just like an attorney (JD) or doctor (MD)) but far and away most engineers, do not have this title, because most engineering jobs and tasks don’t require it.
Finally, (in most states) you can work with no degree under a PE for four years, pass the FE and PE, get your title and build a bridge. So as far as the most stringent title goes, it still doesn’t actually require a degree.
