470 FERDINAND TONNIES : definitions, others held to the given form of mathematics, and thought that the absolute and highest method being impossible for there are primitive words which cannot be defined we must relinquish it, and be content to define all terms of which the meaning is not of itself clear and familiar (cf. Pascal). All were obliged to direct the keenest attention to terminology, and to attempt to lay the foundations which were held to be indispensable. There was a tendency to believe that most disputes between philosophical sects would disappear if only there were unanimity as to the meanings of words. It was assumed therefore and daily experience taught it then as now that many disputants never under- stand each other at all, and that many a one would come to terms with his opponent if he understood him, i.e. if he knew what thought he connected with his expressions : there could hardly be a difference of opinion concerning general facts and their nearest connexions, for an under- standing which was purified from prejudices, and which depended upon the testimony of the senses and some would add upon inner perception (reflexion). The difficulty lay only in the fact that every one gives different names to these facts that is in confusion of language. With more or less outspokenness, with more or less qualification, this was the view of the philosophers of the Aufklarung : Des- cartes, Hobbes, Spinoza, Pascal, and the logician of Port Royal, Locke, Leibniz, Berkeley, Condillac, Wolff, may be named here in a great symphony. Much rarer is the com- plaint that a difference of thought lies hidden under the same expressions. But several of these great authors did not think that the difficulty could be solved by definition alone ; they doubted whether any natural language was suitable for scientific ends. The complaints, which were seconded by less famous names, may be easily referred to the three concepts under which the present treatise has considered the natural social will. They pointed out, (1) that names are given to things on the ground of defective knowledge, according to the impressions of imagination, according to appearance; (2) that the customary use of language is un- certain and inconsequent, that to a large extent it gives expression more to the contradictory feelings and interests of men than to harmonious insight and thoughts, (3) that ordinary speech, but also and especially philosophical terminology, is full of non-literal figurative expressions, whereby confusion and obscurity is exaggerated. The first complaint is directed especially against the classification of organisms. It was the more acute, because according to the
