While I collect my thoughts on some more interesting and current issues, I thought I'd register
my thought on more well-worn abuses in the discussions relating to the sciences (or there unjustified dismissal).
Consider the classical Knowledge Argument from Jackson, which is used to demonstrate the
explanatory gap. In this argument colorblind neuroscientist Mary, who has acquired all of the physical facts of the world and understands everything about the way the brain functions, learns something new when she sees the color red for the first time. In Jackson’s words:
“What will happen when Mary is released from her black and white room or is given a colour
television monitor? Will she learn anything or not? It seems just obvious that she will learn something about the world and our visual experience of it. But then it is inescapable that her previous knowledge was incomplete. But she had all the physical information. Ergo there is more to have than that, and Physicalism is false.”
Before getting into anything, I will register my offense at how the situation is described. This
short and superficial summary of a such a salient issue just makes confusion that much easier. To me this situation is equivalent to offering a boxing ring as an argument against the idea that a circle is always round - "ring" here has only a passing connection to something that is a "circle".
The fact that Mary learns something new when she experiences first person the qualia ‘seeing
red’ is telling in the diagnosis of the mind, because she has been supposed to have already acquired all the knowledge of the mind somewhere in the physical facts of the world. There must be phenomenal truths over and above physical truths (this is reminiscent of Chalmers’ distinction). It follows, then, that the physical or ‘psychological’ method of studying the mind cannot explain conscious experience, and that the explanatory gap is established.
Paul Churchland has argued in several places against the usefulness of this experiment and its
conclusions concerning the mind and consciousness. The problematic claim of the Knowledge
Argument, Churchland believes, is an equivocation of what it means to know something. Specifically, after correctly noting that two distinct ways of knowing (studying as a scientist and experiencing as a conscious person), Jackson carries this into a distinction of the object that is known, inferring that there is also two different things to know. Churchland argues against this, saying that the differences in “ways of knowing” are just two distinct ways of knowing the same object, and nothing more. That is, he believes that though we can grant multiple avenues of epistemic access to a phenomenon, it does not follow from this epistemic plurality that a ontological plurality exists.
Furthermore, the supposed first-person access to the nature of light (via luminance) is a highly
flawed and limited mode of understanding light. This is observed by noting that luminance gives one epistemic access to the visual consciousness of the range of EM waves that can elicit such experiences in the human eye. In other words, we can only understand a fatally narrow range of facts regarding light itself via the first-person experiences of light. Physical study of light, on the other hand, is able to be implemented with none of the weaknesses of first-person experience and with greater yield in explanatory depth and in range of things about light that are explained. Because of this, physical study of the nature of light is a superior means to coming to learn something about light in its ontological form (if anything can). Churchland carries this conclusion to the Knowledge Argument. The two cases have a similar structure. Mary’s experience of the color red is not some gnostic revelation about the nature of light itself, but rather another way of knowing a fact about one object.
Other dualists, like David Chalmers, argue that examples like this miss the point of the Mary thought experiment. The point of phenomenal experience is exactly that it carries special properties that cannot be accounted for in any other experience except from the first person.
However, Since the dualist argument with Mary is first of all based on "knowledge", let's be sure we're not being tricked with what it means "to know" something. Jackson says that we cannot truly know what red is by learning all the relevant physical facts about color and brain processes etc.
Why is this?
The reason is that the dualist assumption of "physical knowledge" is meant to include -propositional knowledge- exclusively! That is, all physical knowledge is expressed with sentence-like structure. This is the reason why the dualist can happily (but falsely) believe that physicalism cannot explain experience - because nothing we can read in a book can tell us what a red rose looks like. This is the horrible trick being played on all philosophers the appearance of Mary; this definition of physical knowledge effectively restricts the representation of the physicalistic thesis to information seen paradigmatically in natural science textbooks. Knowledge of this kind is knowledge at a distance: that is, observations of a certain phenomenon are made by researchers, who express their observations using mathematical formulas and specific descriptions that, among other things, ultimately explain only “the form and function” of that phenomenon, but not its essence. This “text-book” knowledge is hence restricted to a third
person perspective, since those things that (physicalistic) scientific explanations are concerned with ("functional" explanations) are attainable externally to the explanandum.
Does it follow from this that that which is expressed in the language of science is not physical?
Much seems to depend on what it means to” know” something, and so let’s ponder on some ways in which “knowing” something can be cashed out. Propositional knowledge, recall, is knowledge that is expressed in sentential structure, and so can be stored in declarative memory as being the only way "to know". However, there are many things we "know" that are not able to be learned nor expressed in propositional form. This way of "knowing" is just as valid a candidate for knowledge as propositional facts, and more importantly, is used (if only implicitly) for even more things than propositional knowledge; for example, knowing how to ride a bike, knowing how to walk, knowing how to cook.....Are facts described with propositions sufficient to -really- know these things?! I think not. This is the type of knowledge stored in other ways, separate from declarative memory (like in procedural memory, or maybe even episodic memory). Secondly and more importantly, there is no reason to think that this form of knowledge is not physical, and this expands the amount of physical facts that the physicalist can refer to.
Ignoring the various non-propositional forms that knowledge can take, philosophers like Jackson are capable of of kinds of speculative mischief. For purposes of getting published and convincing (non-science) undergraduate students, this is an effective strategy : "Ignore the science, make some stipulations, slather with intuition, draw a conclusion, repeat." Here is an extended excerpt of this strategy in action, taken from Jackson (2004), describing the hidden completeness of our folk acquaintance with some complicated psychological phenomenon:
"What do I mean by implicit knowledge? Consider the situation
logic students are in before they are given the recursive definition
of a wff. Although they cannot specify what it is to be a wff,
they typically can reliably classify formulae into wffs and non-wffs.
Moreover, they can say for any ill-formed formula what triggers
their judgement that it is ill-formed. When presented with “(p v q”,
they do not say that they can see that it is ill-formed but cannot
say where the problem is. They know exactly where the problem is
and how to fix it – add a RH bracket after the “q”. Similarly, they
know what changes to a particular wff would make it ill-formed.
They are in the following position: for each particular example (of
reasonable length), they can say whether or not it is a wff and why,
but they cannot give in words a story that covers all cases. The same
is true for nearly all of us in our judgements of grammaticality.
We can say, for particular examples, whether and why they are or
are not grammatical – this is why “behaviourism” about our grasp
of grammar is a mistake – but we cannot give the general story
in words. Or consider the situation of many bridge players. They
cannot state in detail in a way that goes anywhere near covering all
the cases, the rules of bridge. At the same time, for any given stage
of the game, they can correctly identify the legal moves and what
changes to a given legal move would make it illegal and vice versa,
and in principle (and in practice for the more able ones) critical
reflection on their classifications would allow them to write down
the rules. In this sense, they know the rules implicitly.
I think we should say the same about the sense in which speakers
know the representational properties for words like “water” and
“life”. Consider, for example, the discussions engendered by Twin
Earth scenarios. There is considerable agreement about what to call
“water” and what not to call “water” in these various scenarios. The
impact and importance of the writings of critics of the description
theory of reference derive from this fact, and the same goes for the
considerable agreement about what to call “gold” – and what to call
“Gödel”, “Aristotle” or “life”, if it comes to that. But if speakers can
say what to call “water” when various possibilities are described
to them, we can identify the representational property for the word
“water”: it is the property that, often implicitly, guides them when
they say which stuff, if any, in each possibility to call “water” when
presented with the various scenarios. When the guidance is implicit,
the pattern that underlies the various verdicts will be one they cannot
state in words." (272-3; the section is ironically titled "The Language of the Experts and Implicit Knowledge")
[...]
0 comments:
Post a Comment