Answer:
Well to answer your question... lets first introduce fact.
Natural law theory is based on the 'right or natural thing to do'. This theory was phased into systems of justice after WWII when the many injustices were witnessed against the Jewish community.
Positivism was the prominent theory before this stating that there is no law (not even the moral judgment or power of a higher power) more authoritative than that of law made by man. This had moral complications as witnessed in WWII. These two theories are polar opposites!
It can be seen that natural law and moral judgment or thinking is similar... but not the same. Anyone who says differently clearly has not studied this area of law and foundations!
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http://jw-legaleagle.blogspot.com