A footnote in Amoeba Dick concerning Ockam's Razor

Ockam’s Razor, the lex parsimoniae named after the medieval philosopher William of Ockam, is a methodological – rather than a metaphysical – principle. For a given phenomenon explanandum, the Razor enjoins acceptance of the explanans with the lightest ontological burden.

It is tempting to reformulate the Razor in terms of its impact on the scope of negation in ascriptions about reasonableness of belief. Thus, letting Rϕ be ‘it is reasonable to believe that ϕ’, ‘¬ϕ’ be ‘it is not the case that ϕ’, and → denote material implication, then Ockam’s Razor enjoins us to narrow the scope of negation, i.e. ¬Rϕ → R¬ϕ. That is to say, putting things very loosely indeed, absence of evidence is evidence of absence.