 He was right that our desire for positive facts and things makes us awkward about acknowledging that negative facts or things are the truth-makers of negative truths. Nonetheless, discussions about whether there are truth-makers for a given range of truth bearers on one or the other side of the positive-negative divide are apt to appear nebulous. This is because, as Russell had himself previously noted, there is “no formal test” or “general definition” for being a negative fact; we “must go into the meanings of words” (1918–19: 215–6). Statements of the form “a is F” aren’t invariably positive (“so-and-so is dead”), nor are statements of the form “a isn’t F” (“so-and-so isn’t blind”) always negative. But it doesn’t follow from the fact that a syntactic test cannot be given that there is nothing to the contrast between positive and negative. Molnar suggests that the contrast can be put on a sound scientific footing. For Molnar, natural kinds are paradigm instances of the positive, to be identified on a posteriori grounds (2000: 73). To say that a thing belongs to a natural kind identified in this way is to state a positive fact. To state a negative fact is to negate a statement of a positive fact.