"Phronesis" is concerned with particulars, because it is concerned with how to act in particular situations. One can learn the principles of action, but applying them in the real world, in situations one could not have foreseen, requires experience of the world. For example, if one knows that one should be honest, one might act in certain situations in ways that cause pain and offense; knowing how to apply honesty in balance with other considerations and in specific contexts requires experience.