Abstract
Terrence Deacon, author of Incomplete Nature: How Mind Emerged from Matter, proposes that constraint understood as constitutive absence is a necessary factor in the emergence of life from nonlife, mind from matter. By "constraint" he means "the property of being restricted or being less variable than possible."1 By "absence" he means that constraint is a negative property qualifying a collection or ensemble of constituent parts or members: "It is a way of referring to what is not exhibited, but could have been, at least under some circumstances". By "constitutive absence" he means what is the case "irrespective of whether this is registered by any act of observation". So constraint thus understood is...