Consider a room in parliament where legislation is being enacted. We can describe the objects and events occurring in that room using, as it were, several different languages – different ‘levels’ or realms of discourse – probably all mixed up together: social, psychological, biological, even physicochemical etc. When we talk about these different scientific and linguistic domains (the language and concepts of physics, biology, psychology, sociology etc.) we are inclined to fall back on the hierarchical metaphors of daily life: we use a mental representation of layers or levels . . . as if they were physically superimposed one on another, the layers perhaps interacting causally in ‘top-down’ and ‘bottom-up’ ways. The metaphor encourages us to treat the ‘levels’ as if they were separate physical objects (like the rungs of a ladder, or strata of rock in a geological profile) when clearly we are simply describing the same situation in different ways: we are examining and speaking about the particular situation from different aspects, perspectives, or points of view.
The important point here is that the different descriptions we provide are not descriptions of different objects or existences like superimposed strata of rock. The difference is in mode of explanation (it is epistemological not ontological).
In using the metaphor of hierarchy our logical inferences about the situation follow the logic of the metaphor, in this instance the logic of interacting physical layers.
Principle 2 – following the logic of the hierarchical metaphor we misleadingly treat the world as though it were a series of superimposed and interacting physical layers when, in fact, we simply perceive, understand, and describe the same objects in many different ways
Describing ranks as higher or lower and structuring the world through the metaphor of ranked altitude can therefore be both confusing and unscientific.
So what is it that defines these ‘levels of organization’ – what exactly are their key ranking criteria? What are our intuitions about the nature of these layers?
When we examine this question more closely it emerges that we use at least four classification criteria that blend in a confusing way, so it will help to look at them all in more detail before suggesting an alternative and more scientifically useful language that can achieve the same ends:
a. Size (scale) – objects in the hierarchy are ranked simply larger or smaller: they represent different scales of existence
b. Scope (Inclusion-exclusion, containment) – some objects are contained by, or nested within, other objects. Cells are within tissues, which are within organs, which are within organisms (this is reminiscent of the Linnaeus‘s nested hierarchical classification)
c. Rank value – objects can be arranged in relation to one-another according to some form of valuation
d. Complexity (degree of organization) – ‘levels’ represent irreducible degrees of complexity so, for example, an organism is a highly integrated self-regulating unit, not just an aggregation of molecules.
These criteria (often assumed to lie objectively within the world) correspond to common intuitive (possibly innate) ways of perceiving, representing and understanding the world by size (bigger/smaller), scope or containment (more/less), position (higher/lower) often in combination with value (more important/less important), structure or organization (simple/complex).
The hierarchy of organizational levels seems to blend the Great Chain of Being with the Linnaean nested (containment) hierarchical classification of living organisms.
Do you think that in attempting to build a scientific representation of the structure of the universe that one or several of these criteria better represents the way the world ‘actually is’?