> it is a bit easier to see your muscles than your master's degree when you are walk in a room.

This would make for an interesting experiment.

I bet you can deduce a person's education level accurately by appearance, unless the person makes a deliberate attempt to hide it, but even then, things like good dental hygiene are a give away. People largely try to fit in with their peer group, and people are pretty good at identifying groups.

I think this is especially true with age.