  Throughout his writings, Reinach makes extensive use of the category of states of affairs (Sachverhalte). For example, he maintains that a priori knowledge is first and foremost knowledge of specific states of affairs (e.g., the being equal of 2+2 and 4) rather than of propositions or things. States of affairs may be most accurately described as states of being. This is because it is the being (the copula) in a state of affairs that typically bears the special (for example modal) properties attributed to that state of affairs. For example, in the being equal of 2+2 and 4 it is the being equal that is necessary, just as in the being red of the house it is the being red that is contingent. Similarly, when we assert “that house is not red” we are asserting a state of affairs we have apprehended, namely, the not being red of the house. In this case, the negativity pertains to the copula of the state of affairs, that is, the not being red of the house, rather than the being not-red of the house. There are no negative properties, for Reinach. That is to say, negative properties have no existence, and those philosophers who have posited their existence have been misled by language, which frequently says things are, e.g., not red.