There are no great limits to growth because there are no limits of human intelligence, imagination, and wonder.

There are no such things as limits to growth, because there are no limits to the human capacity for intelligence, imagination, and wonder

Some people wonder all their lives if they've made a difference. The Marines don't have that problem.

It is impossible to underrate human intelligence - beginning with one's own.

I don't think there's anything unique about human intelligence.

We need to make a greater investment in human intelligence.