While Lakatos dubbed his theory "sophisticated methodological falsificationism", it is not "methodological" in the strict sense of asserting universal methodological rules by which all scientific research must abide. Rather, it is methodological only in that theories are only abandoned according to a methodical progression from worse theories to better theories—a stipulation overlooked by what Lakatos terms "dogmatic falsificationism". Methodological assertions in the strict sense, pertaining to which methods are valid and which are invalid, are, themselves, contained within the research programmes that choose to adhere to them, and should be judged according to whether the research programmes that adhere to them prove progressive or degenerative. Lakatos divided these 'methodological rules' within a research programme into its 'negative heuristics', i.e., what research methods and approaches to avoid, and its 'positive heuristics', i.e., what research methods and approaches to prefer. While the 'negative heuristic' protects the hard core, the 'positive heuristic' directs the modification of the hard core and auxiliary hypotheses in a general direction.