Positive law in this way would be one that meets or is effective and is not intrinsically valid (fair) or formally valid (current)! As far as we are concerned we prefer to argue that the terms positive law and Sinner current laws there is no law or rules that remain in force are not positive. Thus we prefer to link the positive with the compulsory and binding nature of law and not with their effective implementation or effectiveness. Positive law is therefore one that can be applied either by the judge, by the Administration or by the citizens themselves. This means that at this point there is a match with the concept of sources and is excluded from this concept that the right will one day be applied, but no longer is, prescisamente, effective and does not apply today, such as Roman law. Natural Law Before expressing any ideas that could be defining the contours of natural law as designed look through history, but not before clarifying that this has been a constant throughout the evolution of law.
In Greece was in Greece where they were born almost all conceptions of natural law and all the philosophical positions against her, which later matured the legal world and supplemented. The Greeks reflected on this topic, realizing the great variety of "positive rights" of existing rules, contradictory applied in the different city states. It would then, that some rules and the same justice were based simply on the interest or convenience of those who imposed? Or rather, there would be above them or guiding guiding principles that established the law and the very idea of fairness? It is clear that many thinkers have adopted positions against the existence of a natural right over the tax by the authority.