And though the Greeks in general say that they are Christians, there is a difference between our belief and theirs. For they say that the Holy Ghost does not proceed from the Son and from the Father, but only from the Father; and they are not obedient to the Pope or to the Roman Church, and they say that the power of the Pope is not greater, on this side of the Grecian sea, than the power of the Patriarch on the eastern side; wherefore Pope John XXII. sent letters to the Greeks to