Are Affordances Plausible? Updating Some Intuitions

In the previous post, I laid out the basic distinction between direct and indirect theories of perception. The basic issue is how to get to behaviourally relevant properties. Such properties of the world have to be partly about the organism, and not just the world; not just 'mass', which is something about the world, but 'moveability' which is something about the world, relative to the organism. If there are properties like these out in the world, and we can perceive them, then perception can, in principle, be direct. If there aren't properties like these there to be perceived, we would have to invent them, and perception would have to be indirect. The ecological hypothesis has to begin by finding behaviourally relevant properties out in the world, ready to be perceived without having to be invented; we need to find affordances. 

The problem is that this seems to be madness, right off the bat. It seems bizarre to think that things separate from the organism could possibly have properties that have anything to do with the organism. Why would they have such things? Surely things can only have properties that are about themselves and make them what they are? 

This post will talk about some pieces of information that make this at least plausible; the next post will talk about the specific ecological hypothesis about affordances that tries to implement that plausibility. To get to that plausibility, I am going to have to update your intuitions about what is simple, and what sorts of things can be physically real, and along the way introduce some useful vocabulary I will do everything I can to use clearly. 

What Does it Mean for Perception to be 'Direct' vs 'Indirect'?

The ecological approach is a theory of direct perception. Put simply, direct perception proposes that our perceptual experience of the world is not mediated by anything that sits between the world and that experience. Making this viable is a big challenge, however, and the idea seems preposterous on the face of it to many people. 

In this post, I want to lay out the basic idea of direct vs indirect perception, and then explain how each approach addresses the problem of how we perceive the world. There will be some big words, but I will aim here to place them in a context that supports them usefully, and focus mainly on the straight-forward ideas in play. In a future post, I will ask the question 'what do we know about how plausible direct and indirect theories of perception are?'