Galileo knew no more than the rest of the world of the secret proceedings of the Inquisition against him and his system. He had only discovered that some Dominican monks wanted to make use of his letter to Castelli to effect the condemnation of the Copernican doctrines, and that they were spreading all sorts of calumnies against him based upon it. Fearing that the copy of it on which they relied might have been tampered with, he sent a correct copy on 16th February, 1615, to his sincere friend Mgr. Dini at Rome, with a request that he would forward it to the mathematician, Father Griemberger, and perhaps even to Cardinal Bellarmine. Galileo observed in the accompanying letter that he had written the one to Castelli “_currente calamo_,” that since then he had made many researches into the subject therein discussed, and announced the speedy completion of a larger work, in which he should carry out his reasoning far more in detail; as soon as it was finished he would send it to Mgr. Dini. (This was his great Apology to the Grand Duchess Christine.) In conclusion, he bitterly complains that his enemies were daily increasing in number, and, in order to injure him the more, were spreading the strange report among the people that he was the founder of the system of the double motion of the earth, which gave rise to incidents like that with Bishop Gherardini.[110] The philosopher, who it is evident was a good deal discomfited, received in reply consolatory assurances from Mgr. Dini and others of his ecclesiastical friends. But they earnestly advised him to treat the subject of the Copernican system purely from the mathematical, physical point of view, and carefully to avoid religious discussion. This hint came rather late in the day, and could not now be of much use to Galileo, when his doctrines were already attacked as heretical, although secretly at that time, and the accusation was based on the purely scientific work on the solar spots. War had been declared with the Copernican system in the name of the Bible. Galileo’s letters to Mgr. Dini of 16th February and 28th March,[111] plainly show how unwillingly he had been driven into the theological field by his opponents. After he had in the second letter decidedly rejected Dini’s suggestion that he should treat the Copernican system merely as a hypothesis, he added that it had been his earnest desire to keep strictly to his part as a man of science, and not to be compelled to defend his astronomical system against religious scruples. He entirely agrees with those who say that the task of bringing natural science into agreement with Holy Scripture should be left to theologians, and shows that he has been compelled to defend himself on this dangerous ground. He says besides that his letter to Castelli was not originally intended to go any farther, and regrets that Castelli had had copies made of it without his knowledge.