  Reinach's views are in this respect opposed to those of Searle (1969), who argued that promising is a social institution that can be explained in terms of so-called constitutive rules analogous to the rules of chess (Zaibert and Smith 2007). Once one stipulates the rules, on this account, then certain necessary truths can be derived. Reinach, in contrast, held that promising is a sui generis phenomenon that is not invented but rather discovered, as is seen in the contrast between promising and those elements of a code of law which truly are constructed, for example specific rules concerning primogeniture or the discharging of liens. Reinach speculates that an individual who orally contracts to rent a piece of property for three years may be surprised to learn that, in German law, this contract is made for an “indefinite length of time.” In contrast, someone who waives a claim will hardly be surprised by the fact that the claim is now extinguished. The latter, in Reinach's terms, flows from the very essence of a claim and of the act of waiving a claim, and in this it contrasts sharply with the non-intuitive arbitrariness of the rules of chess.