from 'On the art of conversation' (Michel de Montaigne)

Meanwhile nothing in stupidity irritates me more than its being much more pleased with itself than any reasonableness could reasonably be.  It is a disaster that wisdom forbids you to be satisfied with yourself and always sends you away dissatisfied and fearful, whereas stubbornness and foolhardiness fill their hosts with joy and assurance.  It is the least clever of men who look down on others over their shoulders, always returning from the fray full of glory and joyfulness.  And as often as not their haughty language and their happy faces win them victory in the eyes of the bystanders who are generally feeble in judging and incapable of discerning real superiority.  The surest proof of animal-stupidity is ardent obstinacy of opinion.  Is there anything more certain, decided, disdainful, contemplative, grave and serious, than a donkey?