One of the most cunning of Satan's wiles is to make those who follow him deny himself. Since at this time those whose minds have been tainted by materialist philosophy in particular have been hesitant in these self-evident matters we shall say one or two things in the face of this stratagem of Satan's.
They are as follows:
There are self-evidently corporeal evil spirits who perform Satan's functions. So too it is certain to the same degree that there are evil spirits without bodies from the Jinns. If they were clothed in physical bodies they would be the same as those evil human beings. Also if those evil spirits in human form were able to leave aside their bodies they would be those Jinn-Satans. Even it is as a consequence of this terrible relationship that one false school pronounced: "After they have died excessively evil spirits in human form become devils."
It is well known that when something of high quality is corrupted it becomes more corrupted than something of less quality does. For example if yogurt and milk go bad they may still be eaten but if oil goes bad it becomes inedible and even like poison. Similarly if the most noble indeed the highest of creatures man is corrupted he becomes more so than a corrupted animal. Like vermin who enjoy the stink of putrefying matter and snakes who take pleasure at biting and poisoning they take pride and pleasure at the evils and corrupt morality of the swamp of misguidance being gratified at the harms and crimes of the darkness of evil-doing; quite simply they take on the nature of Satan. Yes a decisive indication of the existence of devils from the jinn is the existence of human Satans.
Secondly: All the hundreds of decisive evidence proving the existence of angels and spirit beings in this site prove also the existence of evils spirits. We refer this aspect to that Word.
Thirdly: The existence of the angels who are like the representatives and supervisors of the laws of the good matters in the universe are established and agreed upon by all the religions. So too the existence of evil and satanic spirits who are the representatives and ushers of evil matters and the means of the laws of such matters is required by wisdom and reality and is certain. Indeed in evil matters a conscious screen is more necessary. Since everyone cannot see the true good of everything the All-Glorious Creator has made apparent intermediaries as a screen in respect of apparent evils and defects so that objections should not be leveled at Him nor His mercy be accused nor his wisdom criticized or unjustly complained about and so that objections criticisms and complaints should be directed at the screen and not turned to the Generous Creator the Absolutely Wise One. Just as He has made illness a screen to the appointed hour of death in order to save Azrael (the name of angel of death) from the complaints of His servants who die so too He has made Azrael a screen to the seizing of the spirits of the dying so that the complaints at that situation which is fancied to be lacking in compassion should not be directed to Almighty God. And even more certainly dominical wisdom demanded the existence of Satan so that objections and criticisms in the face of evils and bad things should not be directed to the All-Glorious Creator.
Fourthly: As man is a small world the microcosm so is the world a large human being the macroanthropos. Small man is an index and summary of the macroanthropos. The large originals of the samples in man will necessarily be found in the macroanthropos. For example the existence of man's faculty of memory is a certain indication of the existence of the Preserved Tablet in the world. So too everyone has experienced in himself the inner faculty situated in a corner of the heart which is the means to diabolical suggestions and temptations and a satanic tongue which speaks through the prompting of the imagination and the corrupted power of imagination which becomes like a small Satan and acts contrary to its owner's will and opposed to his desires these are certain evidences to the existence of great Satans in the world. And since the inner faculty which is the means to diabolical suggestions and the power of imagination are an ear and a tongue they infer the existence of an external evil individual who blows on the one and makes the other speak.