But what do we understand the pursuit of happiness to mean? For example, does it mean the pursuit of our individual desires, which may appear to be insatiable? But if our individual desires are indeed truly insatiable, then won't the pursuit of our individual desires be insatiable? So what's supposed to be so great about the pursuit of happiness if it insatiable? Pursuing the insatiable sounds like a formula for discontent, not a formula for happiness. Besides that, being subjected to insatiable desires sounds like it would be a challenge to our human freedom. Indeed, it sounds like it would diminish our human freedom if we do indeed have insatiable desires.
Or is it the case that we need to examine our individual desires and learn how to moderate them so that we do not allow them to become insatiable. Moderating our individual desires might enable us to experience satiation of our desires and therefore a modicum of contentment about our satiated desires.
In Plato's famous dialogues the REPUBLIC and the PHAEDRUS, we find a conceptual construct about the human psyche that is composed of three parts: (1) the rational part, (2) the desiring part, and (3) the spirited part (the Greek word is "thumos" or "thymos"). The spirited part of the human psyche is the source of what we today refer to as the fight/flight response.
These three parts of the human psyche parallel the three parts of the triune human brain that Paul D. MacLean identifies as the reptilian brain, the paleo-mammalian brain, and the neo-mammalian brain (the neo-cortex). The neo-mammalian brain is the part of the brain that corresponds to the rational part of the human psyche. The reptilian brain is the part of the brain that controls our fight/flight response. It corresponds to what Plato and Aristotle refer to as "thumos" (or "thymos"). The paleo-mammalian brain is probably the locus in our brains of most of our desires, or the desiring part of the human psyche.
In Plato's PHAEDRUS, we find the famous imagery of a charioteer guiding a chariot drawn by two powerful horses. The horses represent the desiring part of the human psyche and the spirited part ("thumos" or "thymos"). The charioteer represents the rational part of the human psyche, and the chariot itself represents the body.
As to insatiable desires, Plato and Aristotle prescribe the virtue of moderation, defined as the mean between the extremes of over-doing something and under-doing it (e.g., eating).
In addition, Plato and Aristotle prescribed the virtue of courage as the way to cultivate the spirited part of the human psyche ("thumos" or "thymos").