Such was the influence of Porta's work that it remained the authority for the study of Human Physiognomy till towards the end of the 18{th} century when Lavater's four volumes of "Physiognomical Fragments"[160] appeared with their wonderful illustrations, to which the profound impression made by the work was largely due. Lavater constantly refers to Porta, but one of his main objects is to controvert the thesis that the comparison of human features with those of animals should form the means of determining the trait indicated by the feature in question. Curiously enough in a preliminary outline of his system of Physiognomy[161], Lavater had included a chapter on the resemblance between man and animals, but by the time he came to work out his system he had changed his mind and henceforth opposed Porta's view. To be sure, the grounds on which he does so are more of a sentimental than of a scientific character. Lavater--a clergyman and a believer in the special creation of man by the Divine Power (Physiognomische Fragmente II 192),--protests against a possible relationship between man and the animal world, declaring that to see animal features in the human face is to lower the dignity of mankind. Man created as God's supreme achievement can have nothing to do with the animal creation which represents a lower order of being. Even Lavater does not go so far as to deny all resemblances between human features and those of animals. He admits and sympathizes and enlarges on them in several passages (II 192; IV 56); but he ascribes them to accident or to fancy, and declines to draw therefrom the conclusion that the individual who has some feature or a number of features that suggest those of some animal must, therefore, have the traits associated with the animal or the animals in question. It is rather strange that Lavater should not have hit upon the =real= objection to Porta's method which lies in the contradictions in which he necessarily involves himself by comparing the various features of an individual with various animals, the forehead with one animal, the eyes with another, the lips with a third and so on; and since the animals in question show entirely different and contradictory traits, it is manifestly impossible to reach any rational conclusions as to a man's character by so absurd a method. However, although Lavater does not reveal the real weakness of the current theory of Human Physiognomy, yet he contributed to the overthrow of the theory itself which had reached the stage of =reductio ad absurdum= through the modifications introduced by Porta. It often happens that an outlived theory is set aside through arguments that are in themselves insufficient to do so.