Plato has seemed to many to have been scarcely less than the creator of philosophy and it is an immense advance he makes, from the crude or turbid beginnings of scientific enquiry with the Ionians or the Eleatics, to that wide range of perfectly finished philosophical litera ture. His encyclopaedic View of the whole domain of knowledge is more than a mere step in a progress. Nothing that went before it, for compass and power and charm, had been really comparable to it. Plato's achievement may Well seem an absolutely fresh thing in the morn ing of the mind's history. Yet in truth the world Plato had entered into was already almost weary of philosophical debate, bewildered by the oppositions of sects, the claims' of rival schools. Language and the processes of thought were already become sophisticated, the very air he breathed sickly with off-cast speculative atoms.