 It is presumably an adequacy condition on the interpretation of the work of any systematic philosopher that the work be interpreted in light of the central tenets of that philosopher’s system. The interpretive problem of course is that for almost any such philosopher there are controversies about what these central tenets are. It is uncontroversial that Descartes sometimes speaks of possibility and necessity. What is not so uncontroversial is what he is talking about when he talks about these. In particular, if Descartes is committed to the view that there is unactualized possible being, then either (1) the alleged parts of his system that seem to disallow such being are not parts of his system, (2) the parts of his system that seem to disallow such being do not really disallow it, or (3) he is not a wholly systematic philosopher. There is no chance that (3) is right, but much work remains to be done in debates over (1) and (2).