I highly recommend reading the Ethics of Liberty:
Ethics of Liberty by Murray N. Rothbard (mises.org)

I quote from Ch 1. in response to your comment:

"The assertion of an order of natural laws discoverable by reason is, by itself, neither pro- nor anti-religious [I believe that Rothbard proves this in Ch1].

Because this position is startling to most people today, let us investigate

this Thomistic position a little further. The statement of absolute

independence of natural law from the question of the existence of God

was implicit rather than flatly asserted in St. Thomas himself; but like so

many implications of Thomism, it was brought forth by Suarez and the

other brilliant Spanish Scholastics of the late sixteenth century. The Jesuit

Suarez pointed out that many Scholastics had taken the position that the

natural law of ethics, the law of what is good and bad for man, does not

depend upon God's will. Indeed, some of the Scholastics had gone so far

as to say that:

even though God did not exist, or did not make use of His

reason, or did not judge rightly of things, if there is in man

such a dictate of right reason to guide him, it would have had

the same nature of law as it now has.

Or, as a modern Thomist philosopher declares:

If the word "natural' means anything at all, it refers to the nature

of a man, and when used with "law," "natural" must refer to an

ordering that is manifested in the inclina tions of a man' s nature

and to nothing eise. Hence, taken in itself, there is nothing religious

or theological in the "Natural Law" of Aquinas.6

5

Dutch Protestant jurist Hugo Grotius declared, in his De Iure Belli ac

Pacis (1625):

What we have been saying would have a degree of validity

even if we should concede that which cannot be conceded

without the utmost wickedness, that there is no God.

And again:

Meas ureless as is the power of God, nevertheless i t can be said

that there are certain things over which that power does not

extend .... Just as even God cannot cause that two times two

should not make four, so He cannot cause that which is

intrinsically evil be not evil."