Satan is a conjecture because, as a purported individual, nobody I've known has ever met him. Belief based on blind faith, perhaps - but not knowledge.
on the one hand, how do you expect any of those people to have met/meet satan when he is a spirit in the category in which God is?!, on the other hand, the fact that none of the people you have known has ever met satan doesn't mean that he didn't ever appear to anyone else
as for (the) "belief based on blind faith", the fact that you don't understand the truth of the true One doesn't mean no one else understands it
Delusion is caused by a lack of wisdom. If you claim that delusion is created by your evil one, then does the acquisition of wisdom - in the process of dispelling delusion - exorcise him?
who told you that delusion is caused by a lack of wisdom?!
1 Corinthians 1:27-28 "God has chosen the foolish things of the world to confound the wise; and God has chosen the weak things of the world to confound the things which are mighty; And base things of the world, and things which are despised, has God chosen, yes(i.e. to confound the sublime), and things which are not(i.e. that are considered (to be) nothing by the world), to bring to nothing things that are(i.e. things that are considered (to be) something by the world):"
the principal difference is between good and evil rather than (between) wise and unwise, because what if someone is wise (even if wisest) but not good (enough) to save their neighbors needing salvation?!, therefore "wisdom" is not quite the right word, the correct word is rather "righteousness", because:
1 Corinthians 10:24-33 "Let no one seek his own good, but that of his neighbor... Give no offense either to Jews or to Greeks or to the church of God; just as I also please all men in all things, not seeking my own profit but the profit of the many, so that they may be saved.",
1 Corinthians 12:7 "to each one is given the manifestation of the Spirit for the common good.",
1 Timothy 6:3-7 "If anyone advocates a different doctrine and does not agree with sound words, those of our Lord Jesus Christ, and with the doctrine conforming to godliness, he is conceited and understands nothing; but he has a morbid interest in controversial questions and disputes about words, out of which arise envy, strife, abusive language, evil suspicions, and constant friction between men of depraved mind and deprived of the truth, who suppose that godliness is a means of gain. But godliness actually is a means of great gain when accompanied by contentment(i.e. by unfeigned contentment). For we have brought nothing into the world, so we cannot take anything out of it either."
Blessings