People who achieve luxurious lifestyles are rarely satisfied: Experiencing luxury only whets their appetite for even more luxury. In defense of this claim, Seneca asks his friend Lucilius to imagine that he has become magnificently wealthy, that his house has marble floors and is decked with gold, and that his clothing is royal purple. Having all this, he observes, will not make Lucilius happy: “You will only learn from such things to crave still greater.” This is because the desire for luxuries is not a natural desire. Natural desires, such as a desire for water when we are thirsty, can be satisfied; unnatural desires cannot.12 Therefore, when we find ourselves wanting something, we should pause to ask whether the desire is natural or unnatural, and if it is unnatural, we should think twice about trying to satisfy it.