In this paper, I take up one of Wang Yangming’s most audacious philosophical claims, which is that an achievement that is entirely concerned with correcting one’s own inner states, called “establishing sincerity” (licheng 立誠) can help one to fully grasp (jin 盡) all ethically pertinent matters, including those that would seem to require some ability to know or track facts about the wider world (e.g., facts about people very different from ourselves, facts about the needs of plants and animals). (...) Wang makes a claim to this effect in some of his letters and recorded discussions. -/- I begin with a brief, historical reconstruction of what Wang means by “establishing sincerity” and then turn to two sets of controversies regarding his audacious claim. The first has to do with how we should understand the proposal that establishing sincerity helps or positions a person to fully grasp all ethically significant concerns. On the interpretation of Chen Lai 陳來, Wang doesn’t think that establishing sincerity is sufficient by itself to have this grasp, only that it lays a necessary psychological foundation for all attempts to do so, so that it leaves much more work to do. I largely agree with Chen’s reading but find it isn’t strong enough to capture what’s most important and controversial about Wang’s view. On my stronger reading, Wang doesn’t just think that establishing sincerity provides a necessary foundation for a complete grasp, he also thinks that it describes the most difficult and demanding step or part of the process – the other steps come much more naturally and easily. The second set of controversies has to do with whether we can preserve Wang’s core account of virtuous moral agency without his strong ethical nativism, according to which we have an inherent capacity and disposition to track what is ethically important or salient about people and things very much unlike ourselves. I consider some arguments and interpretations of Wang’s thought that might allow us to bypass his nativist presuppositions, and conclude that they do not succeed. Even if we cannot accept his ethical nativism, however, there is a range of important ethical norms for which Wang’s prescriptions are powerful and prudent. The result of this study, I hope, will be an account of Wang’s thought which better positions us to see what parts are (and are not) worth bringing to ongoing debates about the nature of ethics, moral knowledge, and moral virtue. (shrink)