You can't immanentize the eschaton.
Got into a (very) brief debate with Michael Totten about secular humanism, in the comments on this post. Specifically, we were talking about why some conservatives consider Democracy and Education by John Dewey a "dangerous book".
Anyway, it was the first time I'd actually written down my thoughts on secular humanism, so I figured I might as well archive them here, for future reference (and, hopefully, further debate).
Below are the relevant bits.
Secular humanism proposes that man is self-perfectible. That not only does the supernatural not exist, but that the supernatural is unecessary for the fulfilment of man's potential for good. That man has the innate ability to achieve perfect peace and justice, without any external intervention or assistance.
I believe that all of recorded history, and each individual human being that I have ever met or learned very much about, all present compelling evidence that secular humanism is wrong about man. I think it's obvious that there is something profoundly "broken" in man, and that man does not have the innate ability to "fix" that broken thing. Therefore, any philosophy that preaches self-perfectibility is misleading and dangerous.
Take theoretical communism, for example: totally secular, and totally committed to the proposition that man can create a perfect society composed of perfect citizens. But when communism is put into practice, its dangers become manifest. Rather than building a perfect society, secular humanist policies tend to produce some of the worst totalitarian regimes known to man.
If you believe that man is self-perfectible; that greed and hate are aberrations, unnatural and foreign to the human psyche; then how do you explain their persistence throughout history, in the face of the greatest efforts by the wisest men to overcome them? If perfect humans are taught imperfection by flawed societies, then where do flawed societies learn imperfection from? Evil space aliens? It can't be from the perfect people who founded these imperfect societies, can it?