Aesara of Lucania (Αἰσάρα) lived some time during the period 425 B.C. to 100 A.D. An analysis of the language in which she wrote suggests that she is either a “late Pythagorean” (roughly, from the time of Plato), or that she is a “Neo-Pythagorean” (roughly, from the time of Christ) who is attempting to write in an antiquated language and style.

Only a fragment of her work On Human Nature has survived, preserved by the early encyclopedist John of Stobi (Stobaeus, Florilegium, I.49.27).  The fragment is written in Doric prose characteristic of the 3rd century BC or earlier, although that doesn't exclude the possibility that it was written later in an archaic style. It has been argued that the fragment is a Neopythagorean forgery dating from the Roman era, but no evidence is provided for this claim. Moreover, this claim implies that there was an earlier Pythagorean philosopher called Aesara of Lucania whose views were worth imitating.  Other scholars have suggested that the fragment is pseudonymous and comes from a textbook produced by one of the dissenting successor schools to Archytas of Tarentum of Italy in the 4th or 3rd century BC. But there is no evidence for that claim either.  In the absence of any strong evidence supporting either hypothesis, there is no reason to suppose that the fragment was not written by a woman philosopher called Aesara in the 4th or 3rd centuries BC.

A fresco “Lucanian Woman” allegedly depicts her, or, an artist’s imagination of what she looked like. It is reproduced here.

She argues that no one of these parts of the soul ought to dominate, and no part can be dispensed with.  Rather, depending upon the nature of the action, the corresponding part of the soul ought to dominate the others, reigning them in, relative to “the thing to be done.”  For example, if I must choose which food to eat and how much of it to eat, Desire will dominate. If I desire beef, I will choose either a small portion or a large steak.  But Reason will rein in my appetite, so while giving in to the desire to eat beef, reason will tell me that the fat and cholesterol in the steak are excessive threats to my health, and that I ought to choose a small portion.  Spiritedness is the part of the soul that gives me the strength to accommodate my desire in a way that has been mediated by reason, rather than going for the steak.  All three parts of the soul are involved in each decision, but the part that dominates depends upon the task at hand.

Aesara argues that it is by studying our own human nature (and specifically the human soul) that we can understand the philosophical basis for law and morality. Such a view is commonly referred to as “natural law theory.”