I reached Dessau in the hope, that after a few days my friends in Berlin would resolve upon something definite about my work: but in this I was deceived; for, as soon as I turned my back on Berlin, nothing further was thought of the plan. I waited about a fortnight; but when during that period I received no communication, I wrote to Berlin in the following terms:--"If my friends cannot unite upon a plan, they might leave the settlement of it to my own judgment. For my part I believe that, to enlighten the Jewish nation, we must begin neither with history nor with natural theology and morals. One of my reasons for thinking so is, that these subjects, being easily intelligible, would not be able to instil any regard for science in general among the more learned Jews, who are accustomed to respect only those studies which involve a strain upon the highest intellectual powers. But a second reason is, that, as those subjects would frequently come into collision with religious prejudices, they would never be admitted. Besides, sooth to say, there is no proper history of the Jewish nation: for they have scarcely ever stood in political relation with other civilised nations; and, with the exception of the Old Testament and Josephus and a few fragments on the persecutions of the Jews in the middle ages, nothing is to be found recorded on the subject. I believe, therefore, that it would be best to make a beginning with some science which, besides being most favourable for the development of the mind, is also self-evident, and stands in no connection with any religious opinions. Of this sort are the mathematical sciences; and therefore with this object in view I am willing to write a mathematical text-book in Hebrew."