"The exuberant brain is a hopping, electric place, a breeding ground for both invention and rashness. It is by nature impatient, certain, and high on itself; inclined to action rather than reflection; overpromising; and susceptible to dangerous rushes of adrenaline. The exuberant mind is also disinclined to detail, error prone, and vulnerable to seduction. All people, said Walter Bagehot, are most credulous when they are most happy; for someone who is exuberant, self-deception is just the next mountain over from credulousness. All seems possible, much seems essential, and unwarranted optimism feels fully warranted. Self-deception can then move, by conscious intent or not, into the deception of others. ("It is unfortunate, considering that enthusiasm moves the world," said the Earl of Balfour, "that so few enthusiasts can be trusted to speak the truth.")"