prominent place given to physical science in his writings seems to indicate a tendency partly favoured by the circumstances of his birth, partly evoked by the natural progress of the Greek mind in the then stage of its development. This only we know certainly, that at the age of seventeen, about the time when young men in Scotland generally leave school for the university, the future father of encyclopædic science was sent to Athens, where he remained for twenty years as a pupil of Plato in the Academy. But though a pupil, he was anything but a disciple. Naturally of an inductive rather than a speculative habit of mind, and disposed to dissect and to tabulate rather than to collect and to construct, he displayed from year to year a more marked divergence from the great ideal thinker who at that time was impressing his type on the rising intellect of Greece. The reported gossip of antiquity has much to say about some bitter rivalry that arose, and unseemly quarrel that broke out, between the dictatorial master and the independent pupil; but we need believe nothing of this, except in so far as it may be an indication of a radical difference of intellectual character in the two men, which could not but make itself felt in various ways, more or less inconsistent with the relation of a merely receptive and responsive discipleship. Nothing is more common in the intercourse of cultivated men, than that one of the parties finds himself in a condition to respect profoundly what he cannot at all agree with, and what he feels bound, ever and anon, decidedly to controvert. So it fared no doubt with young Aristotle in relation to old Plato. Confluence between two souls so differently constituted there {136} could be none. They cannot be compared as one rose may be compared with another, or even as one flower may be contrasted with another flower, but only as things of a totally different nature, may be named in the same sentence to make their incommensurability more patent. The intellect of Aristotle was a granite palace, that of Plato a garden of paradise; Aristotle’s wit was like a sharp knife and a weighty hammer, Plato’s like a rolling river and a shining ocean; the one bristled with all carious knowledge, the other blossomed with all lofty speculation; Aristotle analysed all things great and small; Plato harmonized all things beautiful and grand. Along with this inborn diversity of intellectual character, we have reason to suppose that there were certain habits of life and social peculiarities about the Stagirite, which were not without offence to the more strict and devoted Platonists. For that there was a certain tinge of Puritanism, and even a sort of lofty pedantry, occasionally manifested in the great architect of ideas, can, I think, scarcely be doubted by any one who has read his great work--the _Republic_--with an unbribed judgment. Now if Plato was somewhat of a philosophical Puritan, in