Our skin is about a millimetre thick.

That's thick enough to protect our soft and vulnerable internal things from most damage.

Yet, far too often, it is not thick enough to protect our soft and vulnerable egos. Somehow, the opinions of others can pierce our thin skin, offend our egos, and distract, dampen, and damage our spirits.

Why does this happen?

How does this happen?

Has this always been the case?

Or -

Did our ancestors have thicker skin?

Did our ancestors view criticism as a noble form of communication? Was there a time when many people, perhaps even whole tribes or communities, had skin that thick?

If so, what happened?

How did people's skin become thinner?

Is it the larger the community the thinner the skin?

Is it the more-advanced the civilization the thinner the skin?

Is it the more the possessions the less the skin?

The more the stuff the less the skin?

And -

Why don't more people take the time to do some self-analysis, obtain some help, and thicken up their skin?

Do people see thin skin as an inevitable part of their destiny...pre-determined, evolution-engineered?

Do they blame their parents, their grandparents, their great-grandparents and so on?

Or - 

Do they wonder - Did our ancestors have thicker skin?