Some - OK, Mary Midgely - just didn't get the metaphor:
Genes cannot be selfish or unselfish, any more than atoms can be jealous, elephants abstract or biscuits teleological.Others apparently propose that these concepts should be ditched. Here is David Sloan Wilson:
Saying goodbye to selfish genes and memes involves questioning everything that has been associated with these concepts and reviving what they seemed to deny: the concept society as organism.I think the concept of "selfishness" is just fine in this context:
The term "selfishness" means promoting your interests without concern for the interests of others. So: "selfish genes" refers to genes promoting their own interests without concern for the interests of other genes - and "selfish memes" refers to memes promoting their own interests without concern for the interests of other memes. If you don't think genes have "interests", recall that referring to "gene interests" is just a shorthand for referring to the propensity of genes to catalyse their own reproduction. Similarly if you don't think that genes can be "concerned" about the interests of other memes, recall that that is just shorthand for actually promoting them.
This raises the issue of to what extent genes and memes are actually selfish. Some genes and memes fail to promote their own interests. Those aren't selfish because they aren't even active - so not all genes and memes are selfish. Most of the mechanisms promoting altruism to others don't apply to genes. Looking at the list of viable explanations for why humans-cooperate most of them don't apply to such entities. Genes and memes could potentially be manipulated into being nice to others of their kind - but it is not easy to come up with cases where this actually happens.
So, is looks as though most selectively-maintained genes and memes are indeed selfish. We could engineer genes or memes that promoted the interests of other genes or memes at their own expense. They could arise by chance mutations. However, such genes and memes are rare. So: the concept of selfishness in this context seems to be both clear and useful.
Another critic is Dan Agin - writing in an aricle entitled Goodbye Selfish-Gene: A New Upheaval in the Science of Human Behavior.
Neither Dan Agin nor David Sloan Wilson seem to have much of a handle on what it means for genes or memes to be "selfish". This is despite David Sloan Wilson's article purporting to unravel the mystery of "What Do Selfish Genes, and Memes, Really Mean?"
Richard Dawkins' idea is fine. David Sloan Wilson fails to articulate a coherent case against the concept - apparently through not groking its intended meaning.
David Sloan Wilson wants to link the concept to group selection. If genes benefitted groups at their own expense they would be behaving less than 100% selfishly. Wilson promotes the idea that group selection is common or important - and so apparently thinks not all genes are 100% selfish. I don't think that was ever the claim in the first place, though. Unselfish genes can arise from mutations - or through the environment changing unexpectedly. The idea is that selfishness is common, not that every single gene is selfish. Anyway, this certainly doesn't a reason for ditching the concept of gene-level selfishness.
It is worth noting that group selection simply doesn't tend to result in "unselfish" genes. While one can imagine genes that are good for groups rather than themselves, group selection would produce genes that are good for themselves that also happen to promote the interests of groups. The crusade against selfish genes in the name of group selection appears to be simply misguided.
Lastly, here is Peter Godfrey-Smith. Peter is the author of a book-length rant against Darwinian agenthood: "Darwinian Populations and Natural Selection". He says "selfish genes" are a "paranoid narrative":
Agential description of evolution can accompany real theoretical progress. This language can be used to quickly express contrasts between theories and models that can then be described more precisely. It can be used to steer the listener away from one family of models and explanations, to another. I don't deny its communicative role, and perhaps a heuristic role in exploring options quickly. In the mid to late 20th century, a change in the application of agential terms to evolution accompanied shifts in evolutionary thinking that were important. Some mid 20th century biology had seen an uncritical treatment of high-level entities, such as groups, species, and ecosystems, as evolutionary units. The reaction against that tendency featured close attention to evolutionary change at the level of individual genes (Hamilton 1964, Williams 1966). Genes became new objects of agential description – tiny and invisible strategists. Two kinds of agential narrative have a special psychological potency. The first is a paternalist schema. Here we posit a benevolent agent, often a large one, who intends that all is for the best. This category includes various Gods, the Hegelian "World Spirit" in philosophy, and stronger forms of the "Gaia" hypothesis, according to which the whole earth is a living organism. The second schema is a paranoid one. Now we posit hidden agents, often small, pursuing agendas that cross-cut or oppose our own interests. Examples include demonic possession narratives, the sub-personal creatures of Freud's psychology (superego, ego, id), and selfish genes and memes. And while it is true that sometimes there are large and kind agents or small and nefarious ones at work, the psychological appeal of these ideas means that we tend to take up such stories too readily and run with them too far. The account of evolution in terms of "selfish genes" (Dawkins 1976) is a paranoid narrative of this kind. It relegates other entities in evolution, such as whole organisms, to the role of mere "vehicles."Dennett wrote a lengthy critique of this kind of material in his book review: Homunculi rule: Reflections on Darwinian populations and natural selection by Peter Godfrey Smith.
I don't have a lot to add to that - though you can see my own review of Darwinian Populations and Natural Selection here
Massimo Pigliucci is another critic of memetic agency - writing in "Memes, selfish genes and Darwinian paranoia":
I must say that I am rarely struck by a novel enough idea that my first reaction is “wow.” This is one of those instances. There is something profoundly intellectually satisfactory in suddenly seeing disparate phenomena like Augustine’s god and Dawkins’ memes as different aspects of an all-too human tendency to project agency where there is none.Alas, many philosophers seem to delight in persistently misundersanding this idea.