Ageing and Longevity (original) (raw)

My aim, in this essay, is twofold. Firstly, I want to characterise ageing as a normative biological process, rather than a purely physical one. This, in effect, means that “ageing” is not a pure wear-and-tear mechanism. In fact, it isn’t even a mechanism, and I’ll explain why I’m critical of the use of that word in biology. It is therefore not accurate, in my view, to define ageing either as a mere imbalance between exergonic and endergonic reactions in the metabolism, as “the free radical theory of ageing” does, or as an imbalance between the excessive formation of reactive oxygen species and the limited amount of antioxidant defences. As we’ll see, ageing is a process, but it is also a constraint, or a set of biological constraints, values, functions, and norms. More specifically, it is a repulsive constraint (1). This means that ageing is not so much a norm, or function, as a normative property. [I will focus on the example of the mammal, and will give an illustration of this point through the example of vicious molecular circles in connective tissues and in mitochondria.] With the expression “normative property,” I mean that ageing is not simply a regulative property. It is a property through which the structure and constraints of a living being are actually transformed. Ageing is not destruction or degradation, but self-destruction. Ageing indicates that biological systems have a tendency to lose their normative power, that is, their ability to change their norms and generate new ones, and to do so in a way that’s regulated. I suggest we refer to ageing thus understood as a process of alteration. Secondly, I want to analyse the relations between ageing and longevity. Not all organisms age, as everybody knows. In worms, yeast, and other organisms, ageing is opposed to longevity, which counteracts the process of self-destruction. If the dynamic of ageing is also self-regulated, how are we to understand the claim, often found in the found in the literature, that longevity “counteracts” ageing (23)?