Academic journal article Analysis and Metaphysics

Functionalism, the Computer Model of the Mind, and Causal Connections

Academic journal article Analysis and Metaphysics

Functionalism, the Computer Model of the Mind, and Causal Connections

Article excerpt

1. Functionalism and the Computer Model of the Mind

The basic idea of funct ionalism is that what makes a state menta l is its playing a causal-functional role of a certain pattern within a system, and, specifically, what makes a mental state the mental state that it is (e.g., its being a belief that it's raining) is its causal connections to perceptual inputs, behavioral outputs, and other mental states. Mental properties, on this approach, are causal-functional properties. The basic idea of the computer model of the mind is that the mind is the software of the body (or the brain), or, in other words, that the mind is to the brain as the program is to the hardware.1 On this model, physical properties and mental properties are properties of the same entity (say a person), it's just that - like software properties of a computer - mental properties belong to a more abstract level. Although not all functionalists employ the terminology of computers, hardware, and software, an important element of the computer model characterizes all versions of the basic functionalist idea, namely the conception of mental properties as abstract high-order properties. Typically, functionalists take mental properties to be abstract properties of physical systems or physical states, namely of brains and brain states.2

Another typical characteristic of functionalist theories is that they allow the possibility of multiple realizations of mental states and properties. That is, according to most versions of functionalism, a mental state of any given type (e.g., feeling pain) may be realized by states of various physical types.3 Further, in pr inciple, a mental state of any given type need not even b e realized physically, and thus the very idea of functionalism is compatible with dualism. As a matter of fact, though, most functionalists believe t hat mental properties are functional properties of the brain, and according to many of them the importance of this theory lies in its ability to account for mental properties and their allegedly unique features in the framework of physica list ont ology. 4 The multiple r ealizability of mental properties is reminiscent of the multiple realizability of software properties, namely of the fact that the sa me soft war e can be realized by computers with differ ent hardwares. This fact too highlights the strong linkage that obtains between functionalism and the computer model of the mind.

2. Two Quandaries

But now a quandary arises. As not ed, functionalism characterizes mental states in terms of their causal connections with perceptual inputs, behavioral outputs, and other mental states. On the other hand, the computer model of the mind does not appeal to causation. Rather, it appeals to abstract characteristics. It seems that t he claim t hat mental properties ar e abstract properties is incompatible with the claim that mental properties are constituted by causal connections, which connections are as concrete as may be. The first quandary, then, is this: how, if at all, can we reconcile the basic tenet of the computer model of the mind - its taking mental properties to be abstract - with the basic idea of functionalism - its taking mental properties to be constituted by causal connections?

Another quandary appears to threaten functionalism. On this theory, mental duplicates (that is, two creatures who share with each other all of their mental properties) share those of their causal powers that are relevant to their mental states. When we combine this feature of functionalism with its allowing for the multiple realizability of mental states, we get the conclusion that utterly different physical objects - for example, my brain and the silicon-based brain of a Martian creature - may be identical in their mentally relevant causal powers. This, however, seems mysterious, for it seems that it is the physical properties of physical objects that are responsible for their causal powers. If so, the question arises of how it is that objects with very different physical makeups may share causal powers. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.