 For discussion of the motivations for this “best system” analysis and its discontents, see the entry on  laws of nature.  Especially noteworthy here are objections which specifically target the role of naturalness in the analysis. The most prominent such objection (van Fraassen  1989;  Loewer  (2007);  Cohen and Callender  2009)  is that the account will make it impossible to know what the laws are, because it will allow for the possibility that even scientists who arrive at true theories by impeccable reasoning nevertheless go wrong in taking the axioms of these theories to be laws, because they are mistaken in thinking that the properties expressed by the basic predicates of these theories are highly natural. This is a hard objection to make stick, since the form of inference involved — from the possibility of error about some question to the conclusion that we are not in a position to know the answer to that question — leads, when generalized, to a rampant scepticism. Non-sceptical epistemologists tend to think that possibilities of error need to meet some further condition of “closeness” or “relevance” in order to undermine knowledge; but it is unclear why one would think that this condition is met in the present case. As we will see in  §4.7  below, natural properties are widely held to be easier to refer to, ceteris paribus. So, arguably, a situation where people ended up with true scientific theories stated in a language whose basic predicates were too unnatural for the axioms to meet the bar for lawhood would have to be quite remote and unusual.