A strong physicalist theory needs to account for not only the physical aspects of objects but also the conceptual nature of everyday experience. There is nothing physical about ethics or our shared social values. There is nothing tangible in the idea of two people conversing (apart from the sound waves generated by air from their lungs passing over their vocal cords). There is, however a relationship between these more abstract ideas and physical objects. Physical and mental levels of existence are interdependent so that if there is a change to one, there is always a change in the other. Supervenience establishes this relationship between mental and physical events. Events have certain properties attributed to them. They occur at a particular time and place, and they consist of certain objects. Instances of physical and mental events must be initiated by a material objects. Therefore, mind-brain identity theory in general is almost universally understood to be a type physicalism theory and not a token physicalism theory. (Kim, pg. 104) This is because of the inherent limitations of token physicalism. Token physicalism asserts nothing more than that mental events “tokens” and physical event “tokens” are instantiated by the same physical event. Because it does not equate them, there is no reason to suppose mind-body supervenience. There doesn’t have to be a specific and reductive relationship between physical and mental events. Mental properties can be free from physical events. Token physicalism doesn’t even address how to explain a mental event. Therefore mental events are unbounded by the physical realm and can have any property imaginable. Rocks can be conscious. Bacteria can have minds. The whole idea of physicalism, according to Kim, is that it must explain mental events in terms of physical events. At the least, it must include a form of mind-body supervenience. Neuroscience relies on this assumption and bases its progress on the fundamental idea that there is an absolute connection between mental and physical events. (Kim, pg 105) Token physicalists, like dualists, reject this connection as a fact and do not believe in the form of reductionism that is entailed in type physicalism. Type physicalists insist that “no Cartesian mental substance” is necessary and that there are no mental facts “over and above physical facts.” (Kim, pg. 105)
(more…)
Posts Tagged ‘physicalism’
Physicalims for the Non-Physicalist – II
Friday, March 12th, 2010Psychoneural Identity Theory, or identity theory, posits that any mental event is equal to a neural occurrence, or some physical event, inside the brain. Jaegwon Kim describes two ways to define what an “event” is. Token physicalism views events as discrete “particulars of the world, along with material objects.” (Kim, Philosophy of Mind, Chapter 4, pg. 101) In token physicalism, a specific mental event “kind” also has a specific physical event “kind”. For example, the action of a hammer hitting my hand is painful, and the painfulness is equal to both the pain itself and the firing of C-fibers in my brain. A second way to define an event is with type physicalism, which states that mental event kinds are equal to physical event kinds and vice versa. Therefore, the hammer hitting my hand is painful, and painfulness is the same as the C-fibers firing in my brain. From this example, it can be shown that type physicalism necessitates token physicalism but token physicalism has no need for the specificity offered by type physicalism. In other words, token physicalism doesn’t actually necessarily mean that the pain I’m feeling is the C-fibers firing, like type physicalism does, it only says that for the particular event of pain that I am feeling, there is the pain and there is also the C-fiber firing. This caveat of token physicalism is what opens the door to dualism and is ultimately why it fails the minimum requirements of a physicalist identity description.
Physicalism for the Non Physicalist – I
Sunday, March 7th, 2010It is no great statement to claim that the human intestinal bacteria known as helicobacter pylori doesn’t have mental states. However, under close inspection, h. pylori can be seen moving towards food, i.e., hydrogen produced in the duodenum. It has also been observed moving away from harm, by tunneling into the intestinal wall in order to move to where the acidic levels of the intestines are lower. To the casual observer, this “moving toward food” behavior and “moving away from harm” behavior might be seen as a sort of awareness – a conscious decision made by the bacteria based on the wish to survive. To a trained scientist however, it’s all a matter of physics. Instead of an ephemeral “mind,” there are chemical reactions occurring within the h. pylori that “reward” the bacteria based on environmental stimuli. For each behavior event, there is a corresponding physical event occurring inside the bacteria. (more…)
