art.” We who know him from his sketches understand him better. In a time in which the authority of the church began to be substituted by that of antiquity and in which only theoretical investigation existed, he the forerunner, or better the worthy competitor of Bacon and Copernicus, was necessarily isolated. When he dissected cadavers of horses and human beings, and built flying apparatus, or when he studied the nourishment of plants and their behavior towards poisons, he naturally deviated much from the commentators of Aristotle and came nearer the despised alchemists, in whose laboratories the experimental investigations found some refuge during these unfavorable times.
The effect that this had on his paintings was that he disliked to handle the brush, he painted less and what was more often the case, the things he began were mostly left unfinished; he cared less and less for the future fate of his works. It was this mode of working that was held up to him as a reproach from his contemporaries to whom his behavior to his art remained a riddle.
