Book 6 opens where moral virtue left off: Aristotle has said the mean is fixed by right reason, but that formula is empty until we know what the right rule actually is. He divides the rational soul into scientific and calculative parts, then names five ways the soul reaches truth: craft, scientific knowledge, practical wisdom, philosophic wisdom, and intuitive reason. Scientific knowledge deals with necessary truths that can be demonstrated; craft is a reasoned capacity to make things that might otherwise not exist; intuitive reason grasps first principles that cannot themselves be demonstrated. The medical analogy returns: knowing what the art prescribes does not yet tell you which medicine to use on this body today.
In the middle, Aristotle distinguishes making from acting. Good action is its own end, while production aims at something beyond itself. Practical wisdom is not science or craft because it deliberates about human goods that could be otherwise. He credits Pericles as someone who sees what is good for himself and for the city, and he notes that young people can excel as geometers long before anyone calls them practically wise, because experience with particulars cannot be rushed. The person who knows only that light meats are wholesome but cannot spot which meat is light will not produce health; the one who knows chicken will.
Later he sorts political wisdom, household management, legislation, and the difference between understanding, which judges, and practical wisdom, which commands action. Cleverness can hit any mark; if the mark is noble, we call it practical wisdom, if base, mere smartness. Vice distorts the starting points of practical reasoning, so wickedness blocks even clear sight of what is worth pursuing. Natural dispositions toward courage or justice resemble virtue but hurt without reason, as a strong blind body stumbles.
He closes by reuniting moral virtue with practical wisdom: virtue sets the right end, practical wisdom finds the right means, and neither is complete without the other. Philosophic wisdom remains higher in rank, concerned with divine and eternal things, yet practical wisdom governs human action without pretending to rule contemplation itself. Sound judgment in life turns out to be a trained union of character and intellect, not a formula you can memorize and apply.
Coming Up in Chapter 7
Book 7 opens on incontinence: how someone can know what is best and still choose worse in the moment. Aristotle distinguishes vice, weakness of will, and brutishness, then asks how appetite can overpower the practical syllogism when it matters most.
