To acknowledge our faults when we are blamed, is modesty; to discover them to one's friends in ingenuousness, is confidence; but to preach them to all the world, if one does not take care, is pride.
Common sense invents and constructs no less than its own field than science does in its domain. It is, however, in the nature of common sense not to be aware of this situation.
In anything that does cover the whole of your life - in your philosophy and your religion - you must have mirth. If you do not have mirth you will certainly have madness.