Thomas Hobbes grounded civil authority in a "natural condition" where creatures could not express themselves through a written language. They could only express their feelings and thoughts through bodily behaviour and this, in turn, led to a nasty, short and brutish life. Once such creatures began to share conventions as to what particular sounds and marks signified, they could agree to abide by certain undertakings. A basic contract could provide the terms and conditions under which all civil officials would enact and interpret their posit of scripts. A command was valid if it could be traced to an institutional office located on a patriarchal structure which, in turn, could be traced to authors who had first acquired a language. Such authors contrasted with the beasts who had dominated the natural condition.