If you want to increase your delusions all you have to do is what delusions do naturally: attempt to rationalize them. Genuinely crazy people have a edge on you, so you gotta start thinking creatively to make up the difference. You are looking for premises which cannot be proven or disproven. Like people who use god exists as a premise, or that good and evil exist as a premise. If they accept those things as truths then they can support any argument they like. Happeh took as his premises that any quality in a picture he looked at, and he wanted to, was a disfiguration. Plus he posited that people do masturbate, and since the statistics show that that is quite common, near universal for men, and due to our societies privacy values concerning it, there is no way that any subject he selected could be proven or disproven to have been masturbating. Using those undisprovable premises, he could support any argument he liked. It isn't scientific, but logical arguments dont need to be scientific, and using logical arguments to build ideas you form working models to base sense and knowledge with.
It is impossible to prove gravity exists, but people accept that it does, and based on other premises like that people have formed the study of physics and all of its principles and workings.