John accordingly resorts to other arguments and to facetious sarcasm to cover his confusion. Then he recovers sufficiently to reiterate his belief that God frequently interferes in the operation of nature by special providences; and asserts that God has been known to change His mind, while the astrologers assert that the stars are constant in their influences. Expressing doubt, however, whether Thomas Becket will be convinced by his arguments, especially the one concerning fate and Providence, or whether he will not laugh up his sleeve at such a clumsy attempt to refute so formidable a doctrine, John lamely concludes by citing Augustine and Gregory against the art, and by affirming that every astrologer whom he has known has come to some bad end,[488] in which assertion he probably simply echoes Tertullian. [Sidenote: Other varieties of magic.] Resuming his discussion of the varieties of magic John briefly dismisses necromancers with the _bon mot_ that those deserve death who try to acquire knowledge from the dead.[489] A number of other terms in Isidore’s list--_auspices_, augurs, _salissatores_, _arioli_, _pythonici_, _aruspices_--he says it is needless to discuss further since these arts are no longer practiced in his day, or at least not openly. Turning to more living superstitions of the present, he explains that chiromancy professes to discern truths which lie hidden in the wrinkles of the hands, but that since there is no apparent reason for this belief it is not necessary to contravert it. [Sidenote: Thomas Becket’s consultation of diviners.] John wishes to ask Thomas one thing, however, and that is what triflers of this sort say when they are interrogated concerning uncertain future matters. He knows that Becket is familiar with such men because on the occasion of a recent royal expedition against Brittany he consulted both an aruspex and a chiromancer. John notes that a few days afterwards Thomas “lost without warning the morning-star so to speak of your race,” and warns him that such men by their vanity deserve to be consulted no more. This gentle rebuke did not avail, however, to wean Thomas entirely from his practice of consulting diviners, which he continued to do even after he became Archbishop of Canterbury. In a letter written to the future martyr and saint in 1170 John again chides Thomas for having delayed certain important letters because he had been “deluded by soothsayings which were not of the Spirit” and exhorts him “So let us renounce soothsayings in the future.”[490] [Sidenote: Witch of Endor: exorcisms.]