Men are four...

A very simple.. yet Lavishly elegant and refined philosophical lines I read goes like this:

Those who know and know that they know. Those possess wisdom, so follow them,

Those who know but don't know that they know. Those are wanderers, so guide them.

Those who don't know and know that they don't know. Those are knowledge seekers, so teach them.

And those who don't know and don't know that they don't know. Those are ignorants, so avoid them.