Lecture 7: Empiricism and the Man in the Inner Room (Turvey, 2019, Lectures on Perception)

The last two Lectures have laid out the mechanical, Cartesian analysis of the problems of perception. Every flavour of this analysis, right up to an including modern representational accounts, rests on 'loans of intelligence', in which important work that's required to make the system work is simply given to the system. For example, Descartes proposes a set of cognitive axioms to ground the inferential processes required to implement knowledge, and makes these innate (specifically, given by God). This won't do - if we want to develop a naturalised theory of perception, we need an account of where every part of the system comes from. 

The Cartesian programme is a form of rationalism, roughly the claim that knowledge is based in reason rather than experience. This chapter reviews the opposing camp of empiricism, roughly the claim that knowledge is based in experience rather than reason. Turvey reviews the approaches of Locke, Berkeley, and Hume, with respect to how they assert a mind can come to know about the world via experience. They end up running into very similar problems as Descartes et al, because of their continued commitment to the mechanistic hypothesis. We are going to have to reject both of these as we progress.

Lecture 6: The Cartesian Program (Turvey, 2019, Lectures on Perception)

Turvey is arguing that modern psychology is still operating within a mechanistic framework, which assumes things like linear chains of causation and predicative properties. In the last lecture, he laid out the kinds of properties this framework allows, and connects his critique of them to the more interesting notions of causation and impredicativity he introduced in Lecture 4. 

In this Lecture, he spells out the way psychology implements the mechanistic framework and identifies that it is, specifically, a Cartesian implementation. Here, we will learn the form of the program, and note how it shows up in the familiar terms of cognitive psychology. 

Lecture 5: The Mechanistic Hypothesis (Turvey, 2019, Lectures on Perception)

In the previous lecture, Turvey spent a lot of time defending the idea that nonlocal causality is a legitimate option for a physical system. He did this by looking at quantum mechanics and the extraordinarily robust evidence it has provided for nonlocality. The reason he did this is because perception as a two-term relation (direct perception) seems to require at least some nonlocal causality in order to work without additional terms (epistemic mediators). 

This chapter is a discussion of properties and how to organise them - ontology. Part of Turvey's work is to lay bare the fact a lot of our science is still working within the 17th century, mechanistic framework - all psychologists have encountered the idea that there are primary and secondary properties of things, and that we are in the business of understanding how the secondary ones work. But, as Turvey is describing, science has moved on, and the possible types of legitimately physical (primary) properties has expanded far beyond what Galileo, etc thought possible. For example, in quantum mechanics, particles don't have properties such as 'position' or 'velocity' until they are placed into a relation with either a position or a velocity measuring device. The property 'position' is impredicative, both defined and actualised by the presence of the relation to a position measurer. Historically, properties that are both defined and actualised by the property holder is in the relation have been considered to be secondary properties; subjective, not objective properties. But quantum mechanics considers particle position to be perfectly real, and it has the extraordinary level of empirical success required to back that claim up. 

This chapter walks the reader through the development of the mechanistic framework that still drives how we classify properties, thus affecting how we study them. It ends by identifying that this taxonomy begins to creak as we use it at the scale of behaviour, and points to the success of quantum physics to suggest a more expansive and interesting taxonomy of real properties is both required and an option. 

Lecture 4: Simulative, Projective, and Locality Assumptions (Turvey, 2019, Lectures on Perception)

This lecture is a brief history of the common assumptions made in theories of perception about how things 'over there' can cause us to have a given perceptual experience. The simulative and projective elements can be quickly dealt with; the big claim in this lecture is that the right notion of causation for perception is non-local, as it is in quantum mechanics. (Note: Turvey is not saying perception is a quantum process. He's just going to use it as a framing to explain what non-local causation is, and he will rely on the rigorous empirical testing it has passed in physics to say it is a viable notion of causation for a physical system.)

Lecture 3: Direct Perceiving, Indirect Perceiving (Turvey, 2019, Lectures on Perception)

In this lecture, Turvey provides a formal definition of what it means to claim a theory of perception is direct vs indirect. A theory of direct perception invokes lawfully specifying information, while all indirect theories invoke at least one mediating physiological or psychological process. Direct theories are allowed to discuss internal states, etc (Gibsonian neuroscience isn't a contradiction in terms), but these states are not allowed to alter information so it is no longer lawfully related to the environment. The big Turvey word we will learn about in this chapter is impredicative entailment - exciting! I'll also briefly point to some implications this chapter has for my recent papers with Sabrina on neuroscience and mechanism.

Lecture 2: Organism-Environment Dualism (Turvey, 2019, Lectures on Perception)

In this Lecture, Turvey lays out the organism-environment dualism that lies at the heart of pretty much all attempts to answer the question, how can an organism come to know about it's environment via perception? He discusses Descartes' mechanistic (mechanical) approach, and then pivots back to the idea that Composition, Environment, Structures (CES) systems are the only approach that can possibly cope with the nature of the problem. 

Lecture 1: What Kind of Systems Do We Study? (Turvey, 2019, Lectures on Perception)

The first thing to do is to characterise what it is we are studying when we are studying perception. Turvey states we are studying epistemic, intentional systems and spends this chapter explaining each term. He does the most work on system; intentional and epistemic are primarily just defined and noted as being features of the system we are going to have to engage with. 

As usual, I will try to efficiently review the key points and then add some reflections on what the chapter made me think about.