proud edifice once offered as the only possible shelter against dangers threatening the very existence of civilisation—we shall be prepared for the application of a similar method to contemporary systems of equally ambitious pretensions; distinguishing that which is vital, fruitful, original, and progressive in their ideal synthesis from that which is of merely provisional and temporary value, when it is not the literary resuscitation of a dead past, visionary, retrograde, and mischievously wrong. And we shall also be reminded that the most precious ideas have only been shaped, preserved, and transmitted through association with earthy and perishable ingredients. The function of true criticism is, like Robert Browning’s Roman jeweller, to turn on them ‘the proper fiery acid’ of purifying analysis which dissolves away the inferior metal and leaves behind the gold ring whereby thought and action are inseparably and fruitfully united. Such, as it seems to us, is the proper spirit in which we should approach the great thinker whose works are to occupy us in this and the succeeding chapter. No philosopher has ever offered so extended and vulnerable a front to hostile criticism. None has so habitually provoked reprisals by his own incessant and searching attacks on all existing professions, customs, and beliefs. It might even be maintained that none has used the weapons of controversy with more unscrupulous zeal. And it might be added that he who dwells so much on the importance of consistency has occasionally denounced and ridiculed the very principles which he elsewhere upholds as demonstrated truths. It was an easy matter for others to complete the work of destruction which he had begun. His system seems at first sight to be made up of assertions, one more outrageous than another. The ascription of an objective concrete separate reality to verbal abstractions is assuredly the most astounding paradox ever maintained even by a metaphysician. Yet this is the central article of Plato’s creed. That body is essentially different from extension might, one would suppose, have been sufficiently clear to a mathematician who had the advantage of coming after Leucippus and Democritus. Their identity is implicitly affirmed in the _Timaeus_. That the soul cannot be both created and eternal; that the doctrine of metempsychosis is incompatible with the hereditary transmission of mental qualities; that a future immortality equivalent to, and proved by the same arguments as, our antenatal existence, would be neither a terror to the guilty nor a consolation to the righteous:—are propositions implicitly denied by Plato’s psychology. Passing from theoretical to practical philosophy, it might be observed that respect for human life, respect for individual property, respect for marriage, and respect for truthfulness, are generally numbered among the strongest moral obligations, and those the observance of which most completely distinguishes civilised