Applying global workspace theory to the frame problem

Abstract

The subject of this article is the frame problem, as conceived by certain cognitive scientists and philosophers of mind, notably Fodor for whom it stands as a fundamental obstacle to progress in cognitive science. The challenge is to explain the capacity of so-called informationally unencapsulated cognitive processes to deal effectively with information from potentially any cognitive domain without the burden of having to explicitly sift the relevant from the irrelevant. The paper advocates a global workspace architecture, with its ability to manage massively parallel resources in the context of a serial thread of computation, as an answer to this challenge. Analogical reasoning is given particular attention, since it exemplifies informational unencapsulation in its most extreme form. Because global workspace theory also purports to account for the distinction between conscious and unconscious information processing, the paper advances the tentative conclusion that consciousness may go hand-in-hand with a solution to the frame problem in the biological brain.

Introduction

The frame problem was originally couched as a difficulty within classical Artificial Intelligence: How can we build a program capable of inferring the effects of an action without reasoning explicitly about all its obvious non-effects? But many philosophers saw the frame problem as symptomatic of a wider difficulty, namely how to account for cognitive processes capable of drawing on information from arbitrary domains of knowledge or expertise. So-called “informationally unencapsulated” processes of this sort, exemplified by analogical reasoning, are especially troublesome for theories of mind that rely on some sort of modular organisation to render them computationally feasible.

However, one thing is clear. If the frame problem is a genuine puzzle, the human brain incorporates a solution to it. In global workspace theory, we find clues to how this solution might work. Global workspace theory posits a functional role for consciousness, which is to facilitate information exchange among multiple, special-purpose, unconscious brain processes (Baars 1997, 1998). These compete for access to a global workspace, which allows selected information to be broadcast back to the whole system. Such an architecture accommodates high-speed, domain-specific processes (or “modules”) while facilitating just the sort of crossing of domain boundaries required to address the philosophers’ frame problem.

The paper is organised as follows. In 2 The frame problem, 3 The computational theory of mind, the philosophers' conception of the frame problem is presented. Section 4 challenges the premise that informationally unencapsulated cognitive processes are, in principle, computationally infeasible. In Section 5, global workspace theory is outlined. Arguments and evidence in favour of the theory are reviewed, and the global workspace architecture is commended as a model of combined serial and parallel information flow capable of overcoming the frame problem.

Section 6 concerns analogical reasoning, the epitome of informational unencapsulation, and demonstrates that the most successful of contemporary computational models of analogical reasoning are strikingly compatible with global workspace theory. The concluding discussion addresses a variety of topics including modularity, conscious information processing, and the relationship between parallel and serial computation in a generic account of cognitive function.