In focusing our attention on the persistence and robustness of living processes we must first address the problem of 'functionality - What is the relationship between 'function' and persistence?' It is commonly thought that a biological process (a cell, for example) within an organism has a function upon which the organism as a whole depends. To illustrate the problem in a simple way let us consider Bugs below. Rabbits perform an important role in the ecosystem. They keep the grass low and thereby create an ecosystem in which certain plants and animals can flourish. However, if we were to suggest to Bugs that he is performing this important function, he may well reply, that the only thing that is important to him is where his next carrot is coming from.

The point is, that Bugs is only really interested in his own persistence as a living rabbit. The consequence of the way in which he lives on the environment is not a 'function' that is explicit in his metabolism.

Bearing this in mind, let us now consider a heart cell. In this instance it might seem quite clear that the heart cell does indeed have a function. However, let us imagine that we remove a heart cell and leave a space where it once was and ask - 'What could live in that space?' One answer to this question is, of course, a heart cell. When we examine biological processes we find that their apparent 'function' is so intimately entwined with their metabolism that they appear to be the same thing. Thus:

Strange as it may seem, the way in which cells and other biological processes survive within the context of a greater organism is, in fact, identical with their supposed functions. Indeed, in cases where people have suffered brain damage, in addition to cell death as a direct consequence of trauma or lack of a blood supply, cells die as a consequence of the fact that they are no longer able to metabolize and so sustain themselves within the neural environment in the same way as they did before the trauma. Neurons that die as a direct consequence of trauma actually comprise the environment that supports the metabolism of other neurons which subsequently die although not directly affected by the trauma themselves.

A more intuitive example of this idea can be instanced by the heart itself. We can look at the action of the heart in two ways. We may choose to see the heart as a functional component of the entire organism, providing oxygen and nutrients for the rest of the body. However, it is often overlooked that the action of the heart is also providing oxygen and nutrients for itself in a way that is reminiscent of a jellyfish.

Given the premise that the apparent function of biological processes is identical to the way in which they maintain their own organization, then, the analysis of living processes in terms of function may be a distraction. The central question we should be addressing is - 'How do metabolic processes maintain their organization over time?' Also, given the intimate relationship between any biological process and its environment we should be looking closely at the relationship between robustness in living processes and those aspects of the environment that form their 'survival space.'