If TSG has a flaw it is IMHO that Dawkins did not fully have the courage of his convictions. When he introduced the concept of a meme he insisted it was just an allegory, an illustrative thought experiment but nothing more. I think this is wrong. I think memes are every bit as legitimately considered alive as genes. This idea has a lot of explanatory power. We humans are hosts not just for genes, but for memes as well, in a sort of symbiotic relationship. Sometimes the interests of our genes and our memes align, such as when we invent antiseptics and antibiotics. Other times they conflict, such as when we invent birth control. The seemingly irreconcilable split between liberals and conservatives could be explained as the beginning of a species split resulting from this conflict, with liberals evolving a bias towards the interests of memes and conservatives biased towards the interests of genes