The phenomenologists were concerned to show that essential structures of being knowable by
rational insight are found far more abundantly than is commonly thought. In his great
monograph Reinach shows that in the civil law where one usually thinks that there are only
legal structures of human devising there are in fact many essential structures such as the
structure of promising or of owning. These pre-positive structures which are something
different from the moral norms relevant to the positive law provide the civil law with a
foundation that can be known by philosophical insight. Though the enactments of the civil law
are changeable these essential foundations are not changeable. Of particular significance and
originality is Reinach's concept of a social act that is of an act that addresses another and
has to be heard by the other in order to be complete. Reinach shows that the essence of legally
relevant acts such as promising comes to evidence when they are understood as social acts. The
concept of a social act in fact has significance far beyond the part of legal philosophy in
which Reinach first discovers it.
