Online research in philosophy

Cognitive agents form beliefs representing the world, evaluate the world as represented, form plans for making the world more to their liking, and perform actions executing the plans. Then the cycle repeats. This is the doxastic-conative loop, diagrammed in figure one.1 Both human beings and the autonomous rational agents envisaged in AI are cognitive agents in this sense. The cognition of a cognitive agent can be subdivided into two parts. Epistemic cognition is that kind of cognition responsible for producing and maintaining beliefs. Practical cognition evaluates the world, adopts plans, and initiates action. There is a massive literature both in philosophy and artificial intelligence concerning various aspects of epistemic cognition, and large parts of it are well understood. Practical cognition is less well understood. We can usefully divide practical cognition into five parts: (1) the evaluation of the world as represented by the agent’s beliefs, (2) the adoption of goals for changing it, (3) the construction of plans for achieving goals, (4) the adoption of plans, and (5) the execution of plans. There is a substantial literature in AI concerning the construction and execution of plans, and I will say nothing further about those topics here. This paper will focus on the evaluative aspects of practical cognition. Evaluation plays an essential role in both goal selection and plan adoption. My concern here is the investigation of evaluation as a cognitive enterprise performed by cognitive agents. I am interested both in how it is performed in human beings and how it might be performed in artificial rational agents.

As a high school student, I rediscovered Hume’s problem of induction on my own. For a while, I was horrified. I thought, “We cannot know anything!” After a couple of weeks I calmed down and reasoned that there had to be something wrong with my thinking, and that led me quickly to the realization that good reasons need not be deductive, and to the discovery of defeasible reasoning. From there it was a short jump to a more general interest in how rational cognition works. I am interested in rational cognition in general. Epistemology is one constituent of rational cognition, practical cognition (rational decision making) another. Much of the work on rational cognition begins with the supposition that only ideal agents can be truly rational. Real agents have limited powers of reasoning and limited memory capacity. It is often supposed that such resource-bounded agents can only approximate rationality, and that as philosophers we should confine our attention to ideal agents. If one wishes, one can of course define “rationality” in this way, but this has never been what interested me. We come to philosophy wondering what we should believe, what we should do, and how we should go about deciding these matters. These are questions about ourselves, with all of our cognitive limitations. For example, it is often claimed that ideal agents, with unlimited cognitive powers, should believe all of the logical consequences of their beliefs. But we, as real resource-bounded agents, cannot do that, so that is not something we should do. What I want to know is how I, as a real agent, should go about deciding what to believe and what to do. Thus my topic is real rationality as opposed to ideal rationality. In the realm of practical decision making, I have explored this distinction at great length in my recent book (2006). Here I will focus on its implications for epistemology. For many years epistemology was derailed by the Gettier problem..

According to the Instrumental Conception of Epistemic Rationality believing rationally is believing in such a way so as to best satisfy one’s cognitive goals. I provide a novel argument against the Instrumental Conception on the basis of an unnoticed phenomenon I call “rational preemption.” You can now revise your plans and actions rationally in order to preempt or prevent foreseeable future irrationality. However, you cannot now revise your beliefs rationally in order to preempt or prevent foreseeable future irrationality. The ability to be preemptively practically rational in your actions and plans, but not preemptively epistemically rational in your beliefs, implies that epistemic rationality is not a species of practical rationality, and thus, ICER is false. (Word Count: 2100).

The theory of rationality has traditionally been concerned with the investigation of the norms of rational thought and behaviour, and with the reasoning procedures that satisfy them. As a consequence, the investigation of irrationality has largely been restricted to the behaviour or thought that violates these norms. There are, however, other forms of irrationality. Here we propose that the delusions that occur in schizophrenia constitute a paradigm of irrationality. We examine a leading theory of schizophrenic delusion and propose that some delusions can be traced to a violation of a condition on thought we call egocentricity. We argue that the violation of egocentricity leads to irrational states that cannot be explained by the traditional categories of irrationality and conclude, therefore, that these states belong in a new branch of the theory of irrationality, that of experiential irralionahly.

Agents are entities that act upon the world. Rational agents are those that do so in an intelligent fashion. What is essential to such an agent is the ability to select and perform actions. Actions are selected by planning, and performing such actions is a matter of plan execution. So the essence of a rational agent is the ability to make and execute plans. This constitutes practical cognition. In order to perform its principal function of practical cognition, a rational agent must also be able to acquire the knowledge of the world that is required for making and executing plans. This is done by epistemic cognition. Rational agents embedded in a realistically complicated world (e.g., human beings) may devote more time to epistemic cognition than to practical cognition, but even for such agents, epistemic cognition is in an important sense subservient to practical cognition.

Although irrationality always presupposes rationality, I think there are good arguments to claim that sometimes rationality presupposes irrationality.This paper tries to show how irrational action can support rationality in two ways: it can develop and preserve rationality. I also argue that sometimes the development and the conservation of rationality can only be realized by irrational action.

Since Gettier, much of epistemology has focused on analyzing “S knows that P”, but that is not my interest. My general interest is in rational cognition — both in what it is to be rational, and in how rational cognition works. The traditional epistemological question, “How do you know?”, can be taken as addressing part of the more general problem of producing a theory of rational cognition. It is about specifically epistemic rationality. I interpret this question literally, as a question about how we should proceed in our epistemic endeavors. Epistemological theories that try to answer this question are theories of procedural epistemology (see my 1998), and when, from this perspective, we assess beliefs in terms of their justifiedness, the concept of justification is one of procedural epistemic justification. Whether this has anything to do with the analysis of knowledge is an open question, and not one that I have much interest in addressing.

* [Irrationality]: ___ Irrationality, like rationality, is a normative concept. Someone who acts or reasons irrationally, or whose beliefs or emotions are irrational, has departed from a standard.