Latest version as of this post, on amazon.com:
I am actually a theist solely because of this book. However, I consider preeminent atheist theoretician Kai Nielsen to be the greatest thinker of all time, and easily the greatest atheist philosopher of all time, because of a single argument he discovered in writing his book Ethics Without God:
Argument from the necessary prior standards of ultimate perfect goodness: We necessarily use prior standards of goodness that are already higher in epistemic authority than God in order to argue that God is good.
Since a being that is merely supremely powerful and intelligent could be evil, no believer in God can get their model for what one ought to be and do from merely knowing that this kind of totally unlimited being exists. And the fact that a supremely powerful and intelligent being issues commands does not by itself invest those commands with moral authority or obligation. Consequently, one must judge in advance---using one's own prior moral as well as intellectual standards---that this being is completely, ultimately, and perfectly good.
No being would be called God unless that being were taken to be, among other things, perfectly good by the person making that judgment. But to properly call this being God, we must already have judged that being to be ultimately good. This proves that our concept of goodness---and our criteria for goodness---are prior to and independent of our belief in the existence of an ultimate and perfectly good transcendent being.
This last can be generalized into an even stronger argument that covers *anything* about God including God's existence per se. Because the standards of analysis are already God-level. Try challenging that statement without assuming it in the process.
The necessary assumptions for inquiring into the matter already rule the mind's operations comprehensively, as an ideal that is necessarily approximated to some extent. (We can always choose to be irrational.) Ultimately as the supervisory court of last resort, exceptionlessly because those assumptions are a set of universals, and just as decisively and authoritatively as God, because they function as the invariant rules of thought for deciding the truth value of any claim or belief or statement whatsoever, including themselves.
In other words, general reason, including logic, common sense, and so on, already has a greater authority than God in order to be the standard for investigating---and passing ultimate and authoritative judgment on---whether the statement that God exists is true.
For theistic apologists, this means that they are using reason as a mind-God in arguing for God's existence at all. And to try to make God rational, in their theological doctrines and controversies, in that sense too God must submit to reason's authority, wear it's badge of approval, have all the proper rational explanations for specific divine policies and actions, and so on.
Christian apologetics in particular is essentially a cognitive worship-fest to reason. This is just one example of the faith/reason schizophrenia, and I'm wondering whether it fosters a kind of cognitive multiple-personality disorder---maybe even damaged DNA---because it's held to be a wannabe theory of knowledge that is logically basic to all thinking.
And for precisely the same reasons, this prior-criteria systems-type issue raises some thorny metatheoretic issues for atheism, agnosticism, and skepticism as well, but I don't think it threatens atheism, only hard or strong agnosticism and unqualified universal skepticism. But in terms of the inferential sequence of logical justification and the general prior method and criteria of analysis itself, atheism wins by default.
God needs reason to be distinguished from heartburn or The Great Pumpkin, but reason stands alone and invincible---it cannot be questioned, denied, doubted, or even thought about without assuming in those processes.
That's the same prior default that believers use to argue their own cases while denying the God-level authority of reason when Oz's curtain is pulled and what they are doing is exposed for what it is.
Atheism needs to drop materialism (whose truth value is eliminated in that reductive process itself as well as the influence-immune supervisory pretensions of that analysis itself, like all universal reductionisms do) and the childish problem of evil (which requires the negation of the intended conclusion in order to provide actual evils in the first place), and learn four arguments extremely well: the burden of proof argument (Angeles' Critiques of God), the insufficient evidence argument (which depends on the burden of proof argument), the incoherence argument against the very concept of God, and the prior independent moral criterion argument and it's generalized form I've mentioned above.
I highly recommend all of Nielsen's writings, especially this book and his 2005 edition of Atheism and Philosophy. which briefly reiterates the above argument that is thoroughly elaborated in Ethics Without God.
Unfortunately, however, for both Nielsen and atheists generally, both the Prior Moral Standard Argument and its generalized Prior Truth Standard Argument (apparently discovered by yours truly in 2006) are theistic Trojan horses.
