"An Agent or a Cause mentally or physically expends energy rendering an Input, whether implicit or explicit, into a Output. Erosion is the work of wind and water on rock. NB: The Input in the case of artistic Output, or an \" artistic work\" as more commonly referred to, is usually INI, because the material at hand being rendered is usually an idea or artistic material that is taken as common foreground knowledge by the semantics of the Agent's professional role. One of Chinua Achebe's greatest works was Things Fall Apart. INI"@en . . "2009-08-11T19:34:29+02:00"^^ . . . . "Labor_product" . . . . . . . . . . . . . . "2164"^^ . .