I can think of several rational reasons why they might prefer to use virus rather than symbiont. For one thing, "symbiont" is probably not part of the active vocabularies of a large part of their intended popular audience, which would certainly make it a less effective metaphor. For another, as Wikipedia states, "the definition of symbiosis is in flux." When I was in high school in the late 80s, the definition we learned had only positive connotations, much like the one still given by Collins Essential English Dictionary: "a close association of two different animal of plant species living together to their mutual benefit."

It’s true: In the popular mind, “symbiosis” connotes win-win, even though it doesn’t technically mean that, much as “virus” connotes win-lose, even though it doesn’t technically mean that. So my proposed replacement for virus was no better than what it was meant to replace; the cure was as bad as the disease. So what term should Dawkins and Dennett use? Yet another reader provided an inspiration:





I completely agree with your post on rational atheists as it is written. But, I was under the impression that clarity in this area is precisely the reason Dawkins adapted the term "meme" to describe an idea that is transferred "virally", but confers an evolutionary advantage on the host.

Actually, no, Dawkins emphatically did not say that a meme by definition confers an advantage on the host. But he didn’t say it confers a disadvantage. In principle, a meme can do either. That’s why, come to think of it, “meme” is the perfect term for religious belief. In fact, when Dennett introduced the term, in the final chapter of The Selfish Gene, he used belief in God as an example of a meme.





Why didn’t Dawkins just stick with this properly neutral analytical term, rather than load the dice with the term “virus”? A theory suggested by my aforementioned post is that back in 1976, when The Selfish Gene came out, he hadn’t yet developed a sense of enmity toward religious believers/belief, but later encounters with them fostered such a sense. So far I haven’t heard a better theory. But I’m sure Dish readers will be happy to fill this void.

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