In the debate over the virus metaphor, many people miss the clear parallels between the human brain and a computer. While many have no problem with the notion that computers can be infected with a metaphorical "virus", it seems that the line is drawn when the human brain is involved. There is abundant evidence that biological viruses can infect and take control of organic brains - controlling them much as a computer virus does. What makes us so resistant to the notion that ideas can do the same thing?
One big objection is that any idea can be a virus (meme) so how does one discriminate between functional and malfunctional mental viruses? How does one discriminate between functional computer software and malware? The nature of malware is to look and act as something functional and useful while going about its nefarious work. If you knew it was malware, you would not let it into your computer.
It seems to me that the same criteria can be used in determining a major piece of human software. Whether it pertains to religion or some other program, the question needs to be answered, does it function to propagate itself, or is it a tool to help the human achieve rational ends. Does it function like a word processor or spreadsheet or does it function as a self replicating parasite, without little regard for its host?
Back to my original question about resistance to the notion of idea control. Mind control is easily demonstrated in a child. It is a simple process to infect a child with ideas that take control of behavior. Growing up, I once watched a grandmother do it quite easily. She simply repeated to her grandchild many times, that the Devil was lurking under the bed, behind the curtains, and people of certain ethnicities. The result was a frequent glance under the bed and behind the curtains for years and an avoidance of certain types of people. Simple superstitious programs are easily placed in the brains of children which then last for years or a lifetime. What is so difficult in seeing a larger more complex program called a religion from infecting a brain and lasting a lifetime, influencing all kinds of behavior.
An infected person would have no idea they were infected any more than an infected computer "knows" it has a computer virus. Unless a computer has a functional virus detection program, the computer cannot detect and rid itself of the virus. A human must have virus detection programs as well. Unfortunately, one of the key strategies of any computer virus or any mental virus is to ensure that it is difficult to detect and that it appears to serve a useful function. Every successful religion does all it can to appear to function in the best interest of the human it infects. In most cases, it is functioning to get that person into heaven or eternal life. If there is an eternal life or heaven, then of course, the program may be functional. If there is no eternal life, then what is the purpose of the "religion program?" Does the program tend to make the person behave in certain ways - like the child looking behind the curtain? The adult equivalent would be to eschew groups with different religious infections, avoid disconfirming evidence of eternal life e.g. evolution, evidence of harmful effects on sexuality, intelligence, etc. A penchant for seeing miracles (invisible god interventions) in the natural world. Denial of scientific explanations for religious phenomenon. Spending time in prayer to the invisible god, when action or planning would be more functional. Talking to invisible beings like angels, gods, devils, etc. Fearing invisible creatures like gods, devils, etc.
In the frame of mental illness, most people would agree that praying to a unicorn, seeing miracles performed by grasshoppers, seeing the hand of Zeus behind daily life events, is probably a sign that the person is infected with some dysfunctional ideas. Ideas that detract from productive living. How is that different from one infected with a Catholic, Mormon or Moslem religious virus?
These are just ramblings and need to be worked more completely, but thought I would put them out for comment or response.