Using such methods as humour, the wise destroy the cherished boundaries between imagination and reality. They throw everything into doubt. By making us attached to reason, the fuel of humour, they deceive us into a false sense of security, while imperceptibly leading us towards liberation. Humour is too strong a weapon for our natural armour, and makes a crack in our shell. Through this crack a serum can be injected - a serum called "reasoning in earnest".
You see, the humour of the wise is fundamentally different from the humour of the world: it is in deadly earnest. When the wise laugh at something, they can never believe in it again. Does one take back one's own spittle having spat it? The worldly wit continually repeats his follies, having no passionate love of reason, seeing reason only as a convenient support for a dreamworld.
We like to listen to the aesthetic, but not to the true. Therefore the wise talk of the aesthetic, tricking us into approaching the true by making us dissatisfied with the aesthetic.