INSTRUCTIONS: See how many puzzles you can solve in Cubism VR. Keep trying even if you get frustrated. After achieving some success, read the following essays and think about how logic, spatial reasoning, and algorithmic thinking are important in successfully completing a specific project. Write a short essay providing three examples of how Occam's Razor works in principle. Feel free to be autobiographical in showing how a simpler (yet accurate and comprehensive) explanation is preferable over a more complex one. Be sure to post on your website and share with your classmates.

Occam's Razor

one should not increase, beyond what is necessary, the number of entities required to explain anything

Occam's razor is a logical principle attributed to the mediaeval philosopher William of Occam (or Ockham). The principle states that one should not make more assumptions than the minimum needed. This principle is often called the principle of parsimony. It underlies all scientific modelling and theory building. It admonishes us to choose from a set of otherwise equivalent models of a given phenomenon the simplest one. In any given model, Occam's razor helps us to "shave off" those concepts, variables or constructs that are not really needed to explain the phenomenon. By doing that, developing the model will become much easier, and there is less chance of introducing inconsistencies, ambiguities and redundancies.

Though the principle may seem rather trivial, it is essential for model building because of what is known as the "underdetermination of theories by data". For a given set of observations or data, there is always an infinite number of possible models explaining those same data. This is because a model normally represents an infinite number of possible cases, of which the observed cases are only a finite subset. The non-observed cases are inferred by postulating general rules covering both actual and potential observations.

For example, through two data points in a diagram you can always draw a straight line, and induce that all further observations will lie on that line. However, you could also draw an infinite variety of the most complicated curves passing through those same two points, and these curves would fit the empirical data just as well. Only Occam's razor would in this case guide you in choosing the "straight" (i.e. linear) relation as best candidate model. A similar reasoning can be made for n data points lying in any kind of distribution.

Occam's razor is especially important for universal models such as the ones developed in General Systems Theory, mathematics or philosophy, because there the subject domain is of an unlimited complexity. If one starts with too complicated foundations for a theory that potentially encompasses the universe, the chances of getting any manageable model are very slim indeed. Moreover, the principle is sometimes the only remaining guideline when entering domains of such a high level of abstraction that no concrete tests or observations can decide between rival models. In mathematical modelling of systems, the principle can be made more concrete in the form of the principle of uncertainty maximization: from your data, induce that model which minimizes the number of additional assumptions.

This principle is part of epistemology, and can be motivated by the requirement of maximal simplicity of cognitive models. However, its significance might be extended to metaphysics if it is interpreted as saying that simpler models are more likely to be correct than complex ones, in other words, that "nature" prefers simplicity.

See also, Occam's Razor:

• as part of the scientific method in the sci.skeptic FAQ.

• in the Encyclopedia Britannica

• in the Physics FAQ

• in the Basic Clinical Skills

SOURCE: http://pespmc1.vub.ac.be/OCCAMRAZ.html

Eliminative materialism (also called eliminativism)

is a materialist position in the philosophy of mind. Its primary claim is that people's common-sense understanding of the mind (or folk psychology) is false and that certain classes of mental states that most people believe in do not exist. Some eliminativists claim that no neural correlates will be found for many everyday psychological concepts, such as belief and desire, and that behaviour and experience can only be adequately explained on the biological level. Other versions entail the non-existence of conscious mental states such as pains and visual perceptions.

Eliminativism about a class of entities is the view that that class of entities does not exist. For example, atheism is eliminativist about God and other supernaturnatural entities; all forms of materialism are eliminativist about the soul; modern chemists are eliminativist about phlogiston; and modern physicists are eliminativist about the existence of ether. Eliminative materialism is the relatively new (1960s-70s) idea that certain classes of mental entities that commonsense takes for granted, such as beliefs, desires and the subjective sensation of pain, do not exist. The most common versions are eliminativism about propositional attitudes, as expressed by Paul and Pat Churchland, and eliminativism about qualia (subjective experience), as expressed by Daniel Dennett and Georges Rey.

Various arguments have been put forth both for and against eliminative materialism over the last forty years. Most of the arguments in favour of the view are based on the assumption that people's commonsense view of the mind is actually an implicit theory, to be compared and constrasted with other scientific theories as to its explanatory success, accuracy and ability to allow us to make correct predictions about the future. Eliminativists argue that, based on these and other criteria, commonsense "folk" psychology has failed and will eventually need to be replaced with explanations derived from the neurosciences. These philosophers therefore tend to emphasize the importance of neuroscientific research as well as developments in artificial intelligence to sustain their thesis.

Philosophers who argue against eliminativism may take several approaches. Some argue that folk psychology is not a theory and should not be compared to one. Others argue that folk psychology is, in fact, a theory and a very successful, even indispensable, one. Another view is that since eliminativism assumes the existence of the beliefs and other entities it seeks to "eliminate", it must be self-refuting.

Overview

Schematic overview: Some sciences can be reduced (blue). Theories that are in principle irreducible are eventually eliminated (orange).

Eliminativism maintains that the common-sense understanding of the mind is mistaken, and that the neurosciences will one day reveal that the mental states that are talked about in every day discourse, using words such as intend, believe, desire, and love, do not refer to anything real. Because of the inadequacy of natural languages, people mistakenly think that they have such beliefs and desires. Some eliminativists, such as the early Frank Jackson, claim that consciousness does not exist except as an epiphenomenon of brain function; others, such as Georges Rey, claim that the concept will eventually be eliminated as neuroscience progresses. Consciousness and folk psychology are separate issues and it is possible to take an eliminative stance on one but not the other. The roots of eliminativism go back to the writings of Wilfred Sellars, W.V. Quine, Paul Feyerabend, and Richard Rorty. The term "eliminative materialism" was first introduced by James Cornman in 1968 while describing a version of physicalism endorsed by Rorty. The later Ludwig Wittgenstein was also an important inspiration for eliminativism, particularly with his attack on "private objects" as "grammatical fictions".

Early eliminativists such as Rorty and Feyerabend often confused two different notions of the sort of elimination that the term eliminative materialism entailed. On the one hand, they claimed, the cognitive sciences that will ultimately give us a correct account of the workings of the mind will not employ terms that refer to common-sense mental states like beliefs and desires; these states will not be part of the ontology of a mature cognitive science. But critics immediately countered that this view was indistinguishable from the identity theory of mind. Quine himself wondered what exactly was so eliminative about eliminative materialism after all.

Is physicalism a repudiation of mental objects after all, or a theory of them? Does it repudiate the mental state of pain or anger in favour of its physical concomitant, or does it identify the mental state with a state of the physical organism (and so a state of the physical organism with the mental state)

On the other hand, the same philosophers also claimed that common-sense mental states simply do not exist. But critics pointed out that eliminativists could not have it both ways: either mental states exist and will ultimately be explained in terms of lower-level neurophysiological processes or they do not. Modern eliminativists have much more clearly expressed the view that mental phenomena simply do not exist and will eventually be eliminated from our thinking about the brain in the same way that demons have been eliminated from our thinking about mental illness and psychopathology.

During the late 1960s and early 1970s, eliminativism gained a wide variety of adherents because of the influence of scientific behaviourism. Proponents of this view, such as B.F. Skinner, often made parallels to previous pseudoscientific theories (such as that of the the four humours, the phlogiston theory of combustion, and the vital force theory of life) that have all been successfully eliminated in attempting to establish their thesis about the nature of the mental. In these cases, science has not produced more detailed versions or reductions of these theories, but rejected them altogether as obsolete. Behaviorists argued that folk psychology is already obsolete and should be replaced by descriptions of stimulus and response patterns. Such views were eventually abandoned. According to Quine and the Churchlands, it will take decades before folk psychology is finally replaced by real science.

Eliminativism is not only motivated by philosophical considerations, but is also a prediction about what form future scientific theories will take. Eliminativist philosophers therefore tend to be very concerned with the data coming from the relevant brain and cognitive sciences. In addition, because eliminativism is essentially predictive in nature, different theorists can, and often do, make different predictions about which aspects of folk psychology will be eliminated from our folk psychological vocabulary. None of these philosophers are eliminativists "tout court".

Today, the eliminativist view is most closely associated with the philosophers Paul and Patricia Churchland, who deny the existence of propositional attitudes (a subclass of intentional states), and with Daniel Dennett, who is generally considered to be an eliminativist about qualia and phenomenal aspects of consciousness. One way to summarize the difference between the Churchlands's views and Dennett's view is that the Churchlands are eliminativists when it comes to propositional attitudes, but reductionists concerning qualia, while Dennett is a reductionist with respect to propositional attitudes, and an eliminativist concerning qualia.

Arguments for eliminativism

Problems with folk theories

Eliminativists such as Paul and Patricia Churchland argue that folk psychology is a fully developed but non-formalized theory of human behavior. It is used to explain and make predictions about human mental states and behaviour. This view is often referred to as the theory-theory, for it is a theory which theorizes the existence of an unacknowledged theory. As a theory in the scientific sense, eliminativists maintain, folk psychology needs to be evaluated on the basis of its predictive power and explanatory success as a research program for the investigation of the mind/brain.

Such eliminativists have developed different arguments to show that folk psychology is a seriously mistaken theory and needs to be abolished. They argue that folk psychology excludes from its purview or has traditionally been mistaken about many important mental phenomena that can, and are, being examined and explained by modern neurosciences. Some examples are dreaming, consciousness, mental disorders, learning processes and memory abilities. Furthermore, they argue, folk psychology's development in the last 2,500 years has not been very significant and it is therefore a stagnating theory. The ancient Greeks already had a folk psychology comparable to ours. But in contrast to this lack of development, the neurosciences are a rapidly progressing science complex that, in their view, can explain many cognitive processes that folk psychology cannot.

Folk psychology retains characteristics of now obsolete theories or legends from the past. Ancient societies tried to explain the physical mysteries of nature by ascribing mental conditions to them in such statements as "the sea is angry". Gradually, these everyday folk psychological explanations were replaced by more efficient scientific descriptions. Today, eliminativists argue, there is no reason not to accept an effective scientific account of our cognitive abilities. If we had such an explanation, then there would be no need for folk-psychological explanations of behaviour, and the latter would be eliminated the same way as the mythological explanations the ancients used.

Another line of argument is the meta-induction based on what eliminativists view as the disastrous historical record of folk theories in general. Our ancient pre-scientific "theories" of folk biology, folk physics and folk cosmology have all proven to be radically wrong. Why shouldn't the same thing happen in the case of folk psychology? There seems no logical basis, to the eliminativist, for making an exception just because folk psychology has lasted longer and is more intuitive or instinctively plausible than the other folk theories. Indeed, the eliminativists warn, considerations of intuitive plausibility may be precisely the result of the deeply entrenched nature in society of folk psychology itself. It may be that our beliefs and other such states are as theory-laden as external perceptions and hence our intuitions will tend to be biased in favour of them.

Specific problems with folk psychology

Much of folk psychology involves the attribution of intentional states (also known as propositional attitudes). Eliminativists point out that these states are generally ascribed syntactic and semantic properties. An example of this is the language of thought hypothesis, which attributes a discrete, combinatorial syntax and other linguistic properties to these mental phenomena. Eliminativists argue that such discrete and combinatorial characteristics have no place in the neurosciences, which speak of action potentials, spiking frequencies, and other effects which are continuous and distributed in nature. Hence, the syntactic structures which are assumed by folk psychology can have no place in such a structure as the brain. Against this there have been two responses: on the one hand, there are philosophers who deny that mental states are linguistic in nature and see this as a straw man argument; on the other, those who subscribe to something like a language of thought assert that the mental states can be multiply realized and that functional characterizations are just higher-level characterizations of what's happening at the physical level.

It has also been urged against folk psychology that the intentionality of mental states like belief imply that they have semantic qualities. Specifically, their meaning is determined by the things that they are about in the external world. This makes it difficult to explain how they can play the causal roles that they are supposed to in cognitive processes.

In recent years, this latter argument has been fortified by the theory of connectionism. Many connectionist models of the brain have been developed in which the processes of language learning and other forms of representation are highly distributed and parallel. This would tend to indicate that there is no need for such discrete and semantically-endowed entities as beliefs and desires.

SOURCE: https://www.cs.mcgill.ca/~rwest/wikispeedia/wpcd/wp/e/Eliminative_materialism.htm