What I am going to tell you next is going to be very irrational, superstitious, yet it is something that I witnessed with my very own eyes -and yes, unlike Descartes, I still believe that something I perceived with my own senses is still somewhat reliable.
Ma was just returning from work when she found something strange in one of our maid. She just sat in the corner of our kitchen, with her hands covering her face, and refuse to made eye contact when we talk to her. Then suddenly she went mad... kiciking and punching everyone, until she was literally rolling on the floor.
My mind refused to admit it, and my eyes just would not believe it, but I have seen someone being possessed. Or in our terms, kesurupan.
The next thing I know, I was struggling to hold her feet so that it would not destroy everything in the kitchen (knives and scissors are being put as far as possible). And two ustadz came and the whole security in the neighborhood came just to held her and try to made her conscious. Or in other words, trying to get rid of the evil being inside.
An exorcism was performed, and during the processed I have seen how the evil spirit refused to left her body, saying that it came from 'far away' and even once asked for a cup of coffee(!!).
In the end, the spirit was successfully being thrown away and my maid returned to herself, alive and healthy (She claimed that that afternoon she saw this huge man approached her and cannot remember anything since). And I was left felling weak ad exhausted, and surprised and shock for what I have just experienced (I especially fear the whole idea of the spirit still exist somewhere and might go for a second try, and there are lotsa stories about the evil spirit 'move' to another victim, and being possessed became somewhat a spreading disease, and evil spirits are the equal of viruses).
It feels funny to experienced such things after reading Tan Malaka's materialism theories.