Invariance

This entry is an attempt to clarify further some terms.

It seems important to appreciate that there are two different types of ‘invariance’ – one spatial, and one temporal.

Eadweard Muybridge

Vernal Falls, Valley of Yosemite, 1872

albumen print

Let’s focus first on constancy over time. How do we identify this in everyday life? We learn to distinguish the enduring state or identity of a thing from the flux of its surroundings. We ‘see’ permanence only in relation to mutability and change.

When Eadweard Muybridge photographs a waterfall in Yosemite his camera records the virtual volume of water occupied over the time interval of the exposure, generating a strange, ghostly image that is decidedly different from the way the waterfall would appear if seen with the naked eye. 

Thanks to photographers such as Muybridge, this type of blurring of the image has become a photographic convention for representing physical motion. We look at this photograph and we recognize the shape formed by the cascade of water as an ‘invariant’. But at the same time – even simultaneously – we see disturbance, flux and flow.

The recognition of temporal persistence is always a process of evaluating between what we see now, and some other moment in the past – one recalled from memory. Each fresh glimpse of anything is only recognizable to us when we can connect it mentally to ‘that’ thing, rather than ‘another’ thing. In other words, when we can say ‘I’ve seen that before’.

This is how we discriminate invariants over time. But identifying invariants over entities is different. To apprehend and acknowledge this we have to abstract a concept, or a standard, from a range of concrete percepts. When we are talking of invariants in this sense, we are really speaking about similarities.

In the case of artists such as On Karawa or Roman Opalka, viewers are invited to recognize instantly the recurring format, and to acknowledge the invariants over their extended series of paintings. 

But that's not all (and this is why the term 'seriality' is not wholly adequate on its own to describe this type of art practice). This is because in their art, spatial invariance is not there purely for the sake of mere appearance. It is to be seen as deriving from another, even more profound level of continuity, namely invariance over time.