It was only natural that such a society should act as a powerful stimulus upon the vivid temperament of Voltaire, who had come to it with the bitter knowledge fresh in his mind of the medieval futility, the narrow-minded cynicism of his own country.  Yet the book which was the result is in many ways a surprising one.  It is almost as remarkable for what it does not say as for what it does.  In the first place, Voltaire makes no attempt to give his readers an account of the outward surface, the social and spectacular aspects of English life.  It is impossible not to regret this, especially since we know, from a delightful fragment which was not published until after his death, describing his first impressions on arriving in London, in how brilliant and inimitable a fashion he would have accomplished the task.  A full-length portrait of Hanoverian England from the personal point of view, by Voltaire, would have been a priceless possession for posterity; but it was never to be painted.  The first sketch revealing in its perfection the hand of the master, was lightly drawn, and then thrown aside for ever.  And in reality it is better so.  Voltaire decided to aim at something higher and more important, something more original and more profound.  He determined to write a book which should be, not the sparkling record of an ingenious traveller, but a work of propaganda and a declaration of faith.  That new mood, which had come upon him first in Sully’s dining-room and is revealed to us in the quivering phrases of the note to Madame de Bernieres, was to grow, in the congenial air of England, into the dominating passion of his life.  Henceforth, whatever quips and follies, whatever flouts and mockeries might play upon the surface, he was to be in deadly earnest at heart.  He was to live and die a fighter in the ranks of progress, a champion in the mighty struggle which was now beginning against the powers of darkness in France.  The first great blow in that struggle had been struck ten years earlier by Montesquieu in his Lettres Persanes; the second was struck by Voltaire in the Lettres Philosophiques.  The intellectual freedom, the vigorous precision, the elegant urbanity which characterise the earlier work appear in a yet more perfect form in the later one.  Voltaire’s book, as its title indicates, is in effect a series of generalised reflections upon a multitude of important topics, connected together by a common point of view.  A description of the institutions and manners of England is only an incidental part of the scheme:  it is the fulcrum by means of which the lever of Voltaire’s philosophy is brought into operation.  The book is an extremely short one—­it fills less than two hundred small octavo pages; and its tone and style have just that light and airy gaiety which befits the ostensible form of it—­a set of private letters to a friend.  With an extraordinary width of comprehension, an extraordinary pliability of intelligence, Voltaire touches upon a hundred subjects