The four most expensive word in the English language are 'This time it's different.
Self-improvement comes mainly from trying to help others.
Three of my children are medical doctors, they know at least a hundred times as much about your body as my grandfather knew, but they don't know much more about soul than he did.
I'm really convinced that our descendants a century or two from now will look back at us with the same pity that we have toward the people in the field of science two centuries ago.