Week 9 Seminar: Alien architecture

A nervous system built on a different plan, and a famous question that may be malformed.

Part III — The control group22 April 2027Week 9 lectureSlidesSchedule

Most of an octopus’s nervous system is not in its brain. The arms carry the majority of its neurons and retain substantial autonomy, which makes the vertebrate question — what does the central controller represent — the wrong first question to ask about it. Godfrey-Smith’s Other Minds is the reading, and Hochner’s 2012 review is the neurobiology.

This is the week where the course’s comparative claim gets its hardest test, because the octopus is not a differently-sized version of the systems in earlier weeks. It’s a different architecture solving overlapping problems.

The question, and the objection#

Nagel asked in 1974 what it is like to be a bat, and the question has done more work in philosophy of mind than almost any other four words. You will read it.

You will also read Akins, who argues the question may presuppose something false — that bat sensory systems are representational in the way the question requires. If they are not, the question isn’t unanswerable so much as malformed, and the difference matters enormously for what we should conclude from our inability to answer it.

Regarding which of these is right, I don’t have a settled view, and the seminar is genuinely open. This is one of two weeks where I will argue against my own lecture.

A problem nobody has solved#

Cephalopods are, as far as we can tell, colourblind. They have one photoreceptor type. They also produce extraordinarily precise colour-matched camouflage.

Stubbs and Stubbs proposed in 2016 that chromatic aberration plus a strange pupil shape could recover spectral information from a single channel. It is ingenious and it is not established. Grade [S] leaning [C], and treat it as a worked example of what a live unsolved problem looks like from the outside — because most of what you will meet in a career looks like this rather than like a textbook.

Reading#

The paper this seminar is built around:

• Nagel (1974). What is it like to be a bat? The Philosophical Review.

The rest of the week’s reading:

• Akins (1996). Of sensory systems and the ‘aboutness’ of mental states. The Journal of Philosophy — the objection, and the harder of the two readings.
• Hochner (2012). An embodied view of octopus neurobiology. Current Biology.
• Stubbs and Stubbs (2016). Spectral discrimination in color blind animals via chromatic aberration and pupil shape. PNAS.
• Godfrey-Smith (2016). Other Minds. FSG — chapters 3–5 this week.

Grades are not attached to papers here, because a grade belongs to a claim rather than to the paper it appears in — see evidence grades. Several of these papers contain claims at two different grades.