In 1625 Descartes returns to Paris from his journey to Italy. There he meets Mersenne, to whom he was very close from that time on, and others of his circle. He soon becomes well-known among them for his works in optics and mathematics and for the scientific method he is developing (during this time he works on the Rules). For instance, on 16 March 1626 Cornier writes to Mersenne, asking him about the work on the refraction of light of that brilliant mathematician he mentioned, and on the 22nd of that month he asks Mersenne to inform him of the excellent method and inventions of Descartes (Rodis-Lewis 1995, p. 63). Descartes' name begins to spread, and other philosophers-scientists are interested in his theories and opinions.