54 FERDINAND TONNIES : thought that he could discover for every idea its characteristic number, so that it would be possible to make all thought just as universal and certain as simple arithmetic mind the calculation of the probability of events, and hence something of the part played to-day m the statistics of population and morality by the figures of births, mortality, marriages, criminality, etc. It is known again how m Logic the attempt at a graphic representation, as also mathematical treatment of concepts, has always been i newed, though hitherto with little success. 90. Many old schemes designed by Reason, which some years ago were still smiled at and rejected as Utopian, jusi as the idea of a universal language is still put aside by rational scepticism, have since then made rapid progress, though they have certainly not been fully realised ; we may think of the universal postal union, of the metrical system for measure and weight, of the Latin coinage convention, of the time for middle Europe, etc. In all these cases we have to do with the relations of symbols to a more comprehensive system, with the determination of units of measurement by a more universal will. In view of these facts we may apply to these dreams, to which thinkers of the highest rank attach themselves, the words which Kant used about the Platonic Eepublic : we should do better to give more attention to this thought, and to throw light upon it by new efforts, than to put it on one side as useless, under the wretched and injurious pretext of impracticability. Such ideas may really act most usefully, they may serve to point the way, though in an unknown land, yet in the direction which promises results. We must will the highest, we must seek the apparently impossible. A system of con- cepts is conceivable, which would present in their natural order all possible ideas in so far as they can have formal value in philosophical judgments, which would establish their relations to one another, their dependence, kinship, con- trast, but would develop all from simple elements which are accepted as belonging to the common consciousness of humanity. These elements, as well as the whole system, should be expressed in an actual language, but in one as far as possible universal (such as Latin; ; and at the same time there should be assigned to them certain linear diagrams, so that complex thoughts could be compounded out of them as geometrical figures plane, spherical and spatial. These lines and figures would not indeed be substituted for the universal term for we continue to think of the term as denoted in language but would illustrate in an easily
