 The recognition of these limits is an enduring feature of Descartes’ ethics. The truths outlined to Elizabeth lay down a set of general guidelines for how to use the will correctly. Following them, however, does not guarantee that we infallibly choose the greatest good; nor is success of this sort required for virtue. As far as virtue is concerned, the critical point is that we do whatever we can to ascertain the best course of action, appealing if necessary to civil law or custom, and that we then will decisively. (For more on this point, see Rutherford 2014.)