Personal integrity

I was reading a checklist for a certain program and came cross a statement that said the person needs to possess high level of personal integrity. I started wondering about that line. What exactly do we mean by personal integrity? Is this something that we learn in school or does the environment around, teaches you integrity. The definition runs closely with our moral compass that we maintain within ourselves. In reality personal integrity is actually what defines who we are and what our moral composition is comprised of. The pillar of integrity gets built brick by brick based on events and incidents we face in our life. We lay the boundaries for ourselves and people around us perceive our whole self based on this very moral fabric we weave ourselves into.

The strongest realization of your own integrity will dawn upon you, when you act it out on your own, without any intervention and without anyone actually witnessing it.

Like returning extra change handed out to you mistakenly by a cab driver. Returning to the rightful owner something that does not belong to you, even when you know that you could have got away with it and no one would have noticed, that would define you as someone with better integrity.