One of the projects of Moses Maimonides in his philosophic and legal writings was to restructure the Jewish tradition around the core concepts of Aristotelian virtue ethics. ¹ He does so in his two large works on ethics: Eight Chapters, an introduction to his commentary on the tractate Avot in the Mishnah, and Laws of Character Traits, a summary and reinterpretation of the ethics of the Jewish tradition in the first book, the Book of Knowledge, of his restatement of Jewish law, the Mishneh Torah. ²

There are certain elements that make it distinctly Aristotelian. First, Maimonides adopts the Aristotelian model of the human soul (psyche) as the form (or “lifeforce”) giving function and organization to the physical matter of the human body. ³ The soul as the form of the body’s matter is neither completely separate nor completely unified with its matter. This model can be differentiated from modern materialism, which envisions the soul as purely physical, or modern dualism which draws no connection between the soul and the body, the soul thus being non-physical. In contrast, the Aristotelian soul has five parts: nutritive, sentient, imaginative, appetitive and rational. The nutritive part includes activities such as physical nutrition, reproduction and growth; the sentient part is the collecting of sensory data using the five senses; the imaginative part stores and reorganizes sensory data; the appetitive part is the source of the emotions and desires; and the rational part is concerned with obtaining knowledge. ⁴ Second, proper human action results from a perfection of certain character traits, which are rooted in the appetitive part of the soul that deals with emotions or temperaments, but can be influenced by reason. ⁵ This appears to be the explanation for why Maimonides refers to the emotions or temperaments as de’ot in the Mishneh Torah, since it has the dual meaning of “character trait” and “knowledge.” ⁶ Third, the different emotions of the soul mimic the larger structure of nature in that they can be seen as a spectrum with two extremes, and the perfected way is the mean. ⁷ For example, courage is the mean between being too fearful and being too rash, or moderation is the mean between taking too much pleasure for oneself and taking not enough pleasure for oneself. The mean is not a static middle position, but differs depending on when one ought, cases in which one ought, toward right people, reasons for the sake of which one ought and the manner one ought. ⁸ Though, Maimonides interestingly does not highlight the role of practical wisdom in deliberating the variability of the mean. Fourth, moral virtues, for Aristotle, are political virtues as they are controlled by a specific law; however, for Maimonides they are cultivated in a more perfect way by a divine law. ⁹ Fifth and last, the highest goal of human life and of the divine law is the pursuit of knowledge for its own sake and for any practical end. Aristotle describes the contemplative life as the highest, most continuous, most self-sufficient and most loved for its own sake, and knowing that God is the first existent is the first commandment in Maimonides’ legal code and the highest human endeavor, represented through the metaphor of the Sultan’s palace. ¹⁰

This book will focus on where Gersonides differs from Maimonides on ethics. Gersonides continues these elements and the focus on the mean as the basis for ethics, but also adds two new categories of individualistic virtues, virtues of self-preservation and virtues of altruism, which transcend the political nature of moral virtues. The virtues of self-preservation arise as a response to “luck” as an unavoidable feature affecting everything in nature. For Maimonides, the ability to avoid the effects of luck is tied to one’s intellectual perfection. He says that “providence watches over an individual endowed with perfect apprehension.” ¹¹ Contrastingly, Gersonides demonstrates that in order to deal with the seemingly capricious element of luck, human beings must focus on virtues in imitation of the nature of animal biology such as endeavor (hishtadlut), diligence (ḥariṣut) and cunning (hitḥakmut) in crafting stratagems (taḥbulot) aiming at physical self-preservation. This also affects certain of Gersonides’ reasons for the commandments as he gives them reasons which are more explicitly connected to self-preservation than in earlier rabbinic discussions. Gersonides’ argument implies that Maimonides did not go far enough and that knowledge must be applied more to virtues that directly focus on the body and not merely knowledge of the whole.

He bases his second model of ethical behavior, which is altruistic in nature, on the human imitation of God, who to his mind, created the laws of the universe for no self-interested benefit. Maimonides and Gersonides derive different lessons from God’s altruism. For Maimonides, the overflow to others is an outcome of one’s own perfection and thus humans imitate God loving-kindness (ḥesed) through necessarily leaving one’s private contemplation to involve oneself in political leadership, especially in legislation where moral virtues are cultivated. Contrastingly, for Gersonides, altruism takes the form of a non-political universal and altruistic ethics whereby humans are obliged to cultivate the virtues of loving-kindness (ḥesed), grace (ḥanina) and beneficence (haṭava) in knowledge and action independent of the state.

These differences between Maimonides and Gersonides also are apparent with regard to the manifestations of self-preservation and altruism on the collective level. For example, Maimonides idealizes the unification of power in the prophet as philosopher–legislator, while Gersonides advocates the benefits of separate institutions parallel to these two models in the political institutions of the kingship, whose primary communal function is ensuring the physical preservation of the political community, and the priesthood, whose primary communal function is altruistically spreading knowledge to the political community. In Gersonides’ model, the prophet takes on the role of challenging and correcting both institutions. This is an important point regarding Gersonides’ philosophy of law, and tells us something about his constitutional thinking. Maimonides also highlights the supreme role of the divine law in minimizing or solving conflicts of values, while Gersonides brings out the greater role for a practical wisdom to deliberate these different conflicts. Gersonides recognizes the conflict between the objectives of physical preservation, achieving peace, and divine commands and he develops a hierarchy of priorities for how to reconcile these competing obligations.

Gersonides’ decision to write on ethics and politics in the form of a biblical commentary is also not accidental. In fact, Gersonides’ commentary is one of the first by an Aristotelian philosopher to provide a successive commentary on most of the Bible, excluding mainly the books named for individual prophets. ¹² Prior to that, as Colette Sirat argues, Jewish Aristotelian philosophers did not see the Bible as a continuous text. ¹³ Indeed, it might even be suggested that his biblical commentary takes the place of writing a supercommentary on Averroes’ commentary on the Nicomachean Ethics and the Republic. ¹⁴ However, he appears to be commenting on the ideas of the Nicomachean Ethics and the Republic both through Averroes’ commentaries on Plato and Aristotle and through Maimonides’ Al-Farabian interpretation of them.

The first element of Gersonides’ biblical hermeneutics is the centrality of narrative. He begins his Introduction to Commentary on the Torah with a justification of the Bible teaching ethics and political philosophy through narratives:

Had the Torah commanded us not to be angry except about what we ought to be angry, about the extent of the anger and about its place and time…and similarly with the other moral qualities and characteristics, then everyone would be in a constant state of sinning, except for a very small [meritorious] few. Moreover, it is inappropriate that such matters should be dealt with by commandments or prohibitions because this would cause people to become lenient in observing the rest of the commandments, since they would see that it is impossible for them to observe many of the Torah’s commandments. Therefore, the Torah has aroused us regarding this part [on political philosophy] by its recounting to us, in their entirety, some of the stories of our ancestors well-known for their perfection concerning their behavior, to direct us to follow in their footsteps and to conduct ourselves in their ways. And along with this it [the Torah] tells us some of the reprehensible actions that were carried out, and the evil end that cam...