The concept of 'Nature' and its Derivatives in the post-human age: a rational or emotive foundation for a legal regulation of new scientific and technological advances?

'Nature' and its derivatives, especially 'Human Nature', are fascinating, albeit very controversial, concepts. Historically, there have been many philosophical and doctrinal proposals for an all-embracing definition of them. However, none of these proposals had a conclusive say on the issue. Indeed, over time, these concepts, especially 'Human Nature', did not become clearer. That occurred not because –as some believe- Human Nature refers or pertains to experience we cannot access (kind of metaphysical dimension) and, therefore, it would offer different unverifiable solutions. Instead, the concept did not become clearer because it cannot be linked to a univocal idea or concept. Indeed, it varied historically and changed intellectual, emotive, social, cultural, and scientific implications and associations that have a simple relationship of contiguity with the concept itself and not of logical interdependence. Despite this fact, in the post-human, legal-philosophical debate we witness to a revival of an all-embracing use of this concept, specifically in relation to legal regulation of new scientific and technological advances, for instance with regard to converging technologies, enhancing technologies, genetic engineering, neuroscience etc. Many think that a regulation of the new techno-scientific advances may be grounded in a comprehensive concept of 'Human Nature', particularly in the revised version of a 'Super Human Nature', as the result of the newest enhancing techniques. Consider, for instance, the ongoing debate on super-human athletes and the question of legalization of doping. This is just one paradigmatic area where we can explore the variety of modes and occasions, in which the idea of conformity or non-conformity to nature is introduced as an element into the ethical appreciation of actions and dispositions. But is 'Human Nature' a rational foundation for a legal regulation within the framework of fundamental rights? Would it protect against discrimination of groups and individuals based on biological, genetic features, or on status, social or personal differences? The paper aims to throw some light on the 'real' reasons hiding behind the efforts to boost the use of determinants, which contribute, in some holistic perspectives, to defining an all-embracing concept of 'Human Nature'. It will be argued that the majority of these attempts have one or more tacit ideological ('ideological' in the sense Kelsen intended this concept) aims, and that a Human Nature based law influences considerably on peculiar, structural features of law. Above all, it impacts negatively on one of the fundamental feature of the modern constitutional approach, that is 'equality in relation to (fundamental) rights'.