The great masters of modern analysis are , , and , who were contemporaries. It is interesting to note the marked contrast in their styles. is perfect both in form and matter, he is careful to explain his procedure, and though his arguments are general they are easy to follow. on the other hand explains nothing, is indifferent to style, and, if satisfied that his results are correct, is content to leave them either with no proof or with a faulty one. is as exact and elegant as , but even more difficult to follow than , for he removes every trace of the analysis by which he reached his results, and studies to give a proof which while rigorous shall be as concise and synthetical as possible.