It is some two hundred years since the existing major political polarities first took shape, approximately the time since the last major revolution in foundational ethics, the overlapping introduction of Kant's principles and also of utilitarianism. Ethical ideas mould social and personal behaviour and expectations profoundly, yet frequently without recognition as cause or catalyst. At the recent UNESCO International Conference on Unity and Diversity in Religion and Culture, one of the authors introduced a new foundational ethical philosophy, the Principle of Goodness ([House 1]). This Principle expresses an ancient intuition about good and evil, which has found expression in the words and deeds of humanity's greatest souls - but always in examples, particulars, or implications, and not, it would seem, as an explicit statement of a grounding philosophical principle until now. As a result, many who respect and advocate what they intuitively see as basic standards of human decency and compassion often find themselves unable to argue successfully for their insights when faced with 'bottom line' or 'big picture' arguments, which use utilitarian or other outmoded theory to 'balance' competing interests - almost always to the disadvantage of the poor, the geographically distant, the numerically small, or the uneducated. By explicitly formulating the 'intuition of the soul', the Principle of Goodness provides a way to expose the intellectual and moral bankruptcy of policies, laws, and systems that ignore the wellbeing of anyone, whatever their situation. The Principle is so oddly familiar that it seems almost trivial (whether one thinks it right or wrong): Goodness is to try to benefit everyone; evil is to try to harm even a single innocent one. And yet, by presupposing this Principle (avoiding the evil and recommending the Good) as the constitutional principle, it is possible to develop non-trivial guidelines for personal, social, and political action and societal development. This is a realist theory of ethics, and the task of this paper is to examine the kinds of consequences for our laws and social systems, which would follow from re-examining their justification and structure in the light of the Principle. The sheer magnitude of this job necessarily means that the coverage must be limited to some basic principles; many connections will remain unexamined. Also, nothing will be said here about the implications for the individual in personal living, although they are also profound and of the utmost importance; that, too, will be addressed in another paper. As a realist theory (briefly, it asserts that Good and evil are realities in the sense that they are summaries of some properties of total Reality), it is essentially empirical rather than deductivist, developing rather than final. As such, our discussion will immediately draw in observable properties of reality and the human condition; these, combined with the Principle, recommend certain kinds of structures (but not just one possible or permissible structure!) as good bases for the development of human flourishing. The outcome of this reconstruction might be considered to have certain features of social systems advocated by both the existing Right and Left but (inherent in the process of development from an independent foundational principle) it is not an amalgam of, or compromise between, these existing political viewpoints.