Condorcet's mind was one of those in which reason preponderates to the exclusion of the imagination, so that whatever could not be definitively proved to his understanding he considered absurd. This texture of intellect, at a time when philosophy was at work to discard, not only the errors of Catholicism, but to subvert Christianity itself, led him to ally himself with men who, while they exerted themselves to enlighten and enfranchise their fellow-creatures from the miseries of superstition, unfortunately went a step beyond, and overthrew, though they knew it not, the boundaries of morals as well as of religion. These men, for the most part, benevolent, studious, and virtuous, believed it easy to lead their fellow-creatures into the same road which they themselves trod; and that, bigotry and superstition being overthrown, persecution would vanish, and mankind live in a brotherhood of peace. Their passions being under their control, they supposed that, could reason be equally developed in all men, they would become, like themselves, dispassionate and tolerant. Condorcet was the intimate friend of D'Alembert; he visited Voltaire with him at Ferney, and was hailed as the youngest and most promising of his disciples. The latter certainly did not possess the calmness and disciplined mind of D'Alembert, but his genius and ardent benevolence brought excuses for the errors of his temper; and Condorcet, while he saw his faults, paid the tribute of flattery which the patriarch of French literature considered his due. As he became intimate with these philosophers, and participated in their views, he began to consider that there were truths of more importance than mathematical demonstrations,--truths that would subvert the impostures of priests, and give men nobler and higher rules of action than those instituted by the papal church. It is the misfortune of Catholicism that, by entangling the absurd and the true, those who throw off its errors are too apt, without examination, to cast away the truths which it has overgrown and distorted; but which minds of truer discernment can see and acknowledge. Condorcet, on first engaging in the labours of moral philosophy, took the easier path of refuting others, rather than developing novel ideas of his own. His application and his memory had caused his mind to be richly stored with every kind of knowledge--add to this he was a profound logician. His first work of polemical philosophy was a refutation of the "Dictionnaire des Trois Siècles," by Sabathier de Castres. He assumed the epistolary form of argument, which is at once the easiest, and affords the fairest scope for the various arms of ridicule and reasoning. Voltaire hailed his work with delight, and bestowed a degree of praise highly encouraging to the young author.