There is no objective basis for morality.

I too find interest in this subject and may we both enjoy a mutual moral exchange of ideas. The goal of a “moral” mutual exchange of ideas is when we both receive positive feedback from the learning experience during the exchange. Morality is an outgrowth of life's Unalienable Rights, which is an outgrowth of the physical Constructal Law, which is an outgrowth of the Laws of Thermodynamics. Morality is part of the physical Laws of Nature, not metaphysical. Please bear with me as we take a journey following the traceable path from Thermodynamics (moments after the Big Bang) to Morality. The Laws of Thermodynamics deals with the direction of energy flow. Constructal Law deals with patterns generated by the dynamics of energy flow, within a space that can freely morph relative to resistance, presents configuration during the evolution of biology, physics, technology and social organization. At the biological level once alive, “Life,” must have the freedom (“Liberty” in the optimization relative to resistance), in “the pursuit (energy flow) of” survival; otherwise, there is no life. Since we have life, survival is a form of positive feedback and a prerequisite for human “Happiness.” Hence, Thomas Jefferson's discovery, which he declared “self-evident” and used the label “Unalienable Rights” representing a polished version of this bio-program, pertaining to the flow dynamics of life, in his following celebrated statement, “Life, Liberty, and the pursuit of Happiness.” The following is a video overview of the Constructal Law:http://www.youtube.com...The following video shows Unalienable Rights are a manifestation of the Constructal Law. Now that we got that out of the way.Let's go back to your Island where you stated the following:“The island and the surrounding ocean provide a wide variety of resources and I am able to use my reason and my ability to think to devise ways of turning theses resources into things that I need to live, e.g. I make tools for gathering and/or hunting food, I devise means of collecting and storing fresh water, I discover or construct shelter.” Whether you knew it or not, you are trapped within the matrix of the Laws of Nature, the set of omnipotent “objective” Laws, the basic “phenomenon” found throughout Nature. In other words, for you to make tools, collect water, construct a shelter, you must morally follow those Laws in Nature to obtain positive feedback relative to accomplishing your goal. If you immorally go against those Laws you will failed in making tools, collecting water, and construct a shelter. Now it comes down to that “man” in question. It was obvious that your goal was to kill that man. You morally followed the Laws of Nature to fulfill your goal. And as a result, you most likely receive positive feedback from your accomplished goal. In conclusion, for life to survive (Pro's island example) or to pursue any goal, it must morally follow the Laws of Nature, those omnipotent “objectives, phenomenon,” the basis found throughout Nature, "independent of individual thought;" otherwise, an immoral action will result in failure. And from this thesis I conclude: There is objective basis for morality.