Sentence:  Life is further characterized , in antithesis to Piepsam , as animal : the image of a dog , which appears at several places , is first given as the criterion of amiable , irrelevant interest aroused by life considered simply as a spectacle : a <WSD>dog</WSD> in a wagon is `` admirable '' , `` a pleasure to contemplate '' ; another wagon has no dog , and therefore is `` devoid of interest '' . 
Meaning of the word marked with <WSD> tags:  a member of the genus Canis (probably descended from the common wolf) that has been domesticated by man since prehistoric times; occurs in many breeds