Beyond old dichotomies: empiricist/nativist empiricist/rationalist

Aaron Sloman

Abstract

Concept empiricists think it is blindingly obvious that concepts cannot come from anywhere except experience of sensed instances of concepts. Some modern concept empiricists call this 'symbol grounding theory'.

Nativists (e.g. Immanuel Kant) think it is obvious that you can't have any experiences unless you already have some concepts (e.g. having spatial experiences requires some sort of understanding of spatial relations (higher, lower, left, right, inside, outside, near, far, etc.) and also the ability to grasp differences of spatial content, e.g. colour, texture, etc.

A rationalist objection to concept empiricism is that structural relationships (e.g. Carnapian 'meaning postulates') between symbols, within a theory embedded in a reasoning system, make a significant contribution to meaning (as a formal axiom system determines a class of possible models, restricting the class more as extra axioms are added. An extreme view is that a sufficiently rich structure can determine most of meaning, requiring only a few 'attachment points' through sensory and motor transducers to pin down reference to the actual world.

(Compare: Quine, in Two Dogmas of Empiricism:

"The totality of our so-called knowledge or beliefs, from the most casual matters of geography and history to the profoundest laws of atomic physics or even of pure mathematics and logic, is a man-made fabric which impinges on experience only along the edges. Or, to change the figure, total science is like a field of force whose boundary conditions are experience.)

A more recent contribution is the biological view that individuals need not learn so much through their experience because each of us starts with the benefit of millions of years of learning -- by the species and its precursors. But there are different cases. Precocial species, whose infants/larvae etc. have to be relatively self-sufficient immediately after birth or hatching (chickens, deer) clearly must get their initial competence via the genome even if it gets refined and extended by each invidual over time -- unlike members of altricial species, which start off more or less helpless and utterly dependent on elders for food, shelter, etc.

It does not follow that the altricial species (e.g. humans, nest-building birds, hunting mammals) start off with nothing innate: it may be that what they have innately is far more subtle, powerful, general, abstract -- and rich in higher order meanings than what the precocial species have.

So my question is: what could that be? It would have to be some kind of bootstrapping mechanism in an architecture that grows itself while it interacts with the world to find out which of the potential growth trajectories it should follow. On that view some, but not all, of the actual growth will be innately determined. For precocial species almost all is innate and structurally determined.

On this view someone born blind from birth because of peripheral deformities, but with a normal brain, could have much of the apparatus required for colour concepts, which may explain how so many blind people can have conversations about colours, contrary to the expectations of concept empiricists with normal vision.

I'll sketch some requirements for an explanatory theory and working model that might fill out these ideas. However I have more questions than answers.