by following the natural law, human beings can achieve the most peaceful, prosperous, fulfilling, and happy lives conceivable - even by *their own definitions..minimizing conflicts among men, advancing technological progress..., etc..Your assertion natural law is good because it achieves these results. Obviously, the truth of your statement is conditional - based on whether these are good.
You have merely moved your absence of "proof" to another point, which you haven't proven, or even as yet given reason, that these are good.
I too believe these are "good." in general. However if we are not to rely on the sphere of religion (absolute/non-conditional - with or without a diety), we have to stick to the rational, the only tool we have in your stated method is reason/logic.
That means you still have to provide the proof for these values upon which you've conditioned the truth of the value of 'natural law'.
In order to follow your stated method, you need to give the reason why, for example: "advancing technological progress is better than not advancing technological progress."
We may or may not agree on whether this value is "good," but either way, a system solely based reason, requires more.
You wrote: “That means you still have to provide the proof for these values upon which you’ve conditioned the truth of the value of ‘natural law’.”
The values which I have listed are good because they are ultimately conducive to securing the life of every human being and creating conditions where this life in increasingly less subject to the perils of both the natural world and the world of other men.
So, if we take my argument far enough, we will find that it hinges on the following proposition: “Living life is superior to not living life.”
This is a proposition which reason itself compels all human beings to agree to — because it is a proposition which they implicitly embrace in the process of arguing or even in the process of living itself. If it is logically impossible to escape the implicit choice to live, then we have our basis for a rational, secular morality.
I illustrate why this is in “The Implicit Decision to Live: The Immorality of Suicide and Forced Termination of Life”
http://www.associatedcontent.com/article/280318/the_implicit_decision_to_live_the_immorality.html
If life is good, then progress and peace and liberty are good, which implies that the natural law — which brings all these about — is good.
I am
G. Stolyarov II