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Belief

Belief in the psychological sense, is a representational mental state that takes the form of a propositional attitude. In the religious sense, "belief" refers to a part of a wider spiritual or moral foundation, generally called faith.

Belief is considered propositional in that it is an assertion, claim or expectation about reality that is presumed to be either true or false (even if this cannot be practically determined, such as a belief in the existence of a particular deity).

Historically, philosophical attempts to analyze the nature of belief have been couched in terms of judgement. Both David Hume and Immanuel Kant are both particularly well known for their analyses using this framework.

Table of contents

1 Belief, knowledge and epistemology 2 Belief as a psychological theory 3 Is belief voluntary? 4 Delusional beliefs 5 See also

Belief, knowledge and epistemology

To believe something can be interpreted as assigning a probability of more than 50% that something is true. The rule of the thumb from a school of epistemology that says that certainty should be as big as the corresponding evidence is called evidentialism.

Belief as a psychological theory

The concept belief presumes a subject (the believer) and an object of belief (the proposition) so like other propositional attitudes, belief implies the existence of mental states and intentionality, both of which are hotly debated topics in the philosophy of mind and whose foundations and relation to brain states are still controversial.

Beliefs are sometimes divided into core beliefs (those which you may be actively thinking about) and dispositional beliefs (those which you may ascribe to but have never previously thought about). For example, if asked 'do you believe tigers wear pink pyjamas ?' a person might answer that they do not, despite the fact they may never have thought about this situation before.

The idea that a belief is a mental state is much more contentious. While some philosophers have argued that beliefs are represented in the mind as sentence-like constructs others have gone as far as arguing that there is no consistent or coherent mental representation that underlies our common use of the belief concept and is therefore obsolete and should be rejected.

This has important implications for understanding the neuropsychology and neuroscience of belief. If the concept of belief is incoherent or ultimately indefensible then any attempt to find the underlying neural processes which support it will fail. If the concept of belief does turn out to be useful then this goal should (in principle) be achievable.

Philosopher Lynne Rudder Baker has outlined four main contemporary approaches to belief in her book Saving Belief:

• Our common-sense understanding of belief is correct - Sometimes called the ‘mental sentence theory’, in this conception, beliefs exist as coherent entities and the way we talk about them in everyday life is a valid basis for scientific endeavour. Jerry Fodor is one of the principle defenders of this point of view.
• Our common-sense understanding of belief may not be entirely correct, but it is close enough to make some useful predictions - This view argues that we will eventually reject the idea of belief as we have use it now, but that there may be a correlation between what we take to be a belief when someone says 'I believe that snow is white' and however a future theory of psychology will explain this behaviour. Most notably philosopher Stephen Stich has argued for this particular understanding of belief.
• Our common-sense understanding of belief is entirely wrong and will be completely superseded by a radically different theory will have no use for the concept of belief as we know it - Known as eliminativism, this view, most notably proposed by Paul and Patricia Churchland), argues that the concept of belief is like obsolete theories of times past such as the four humours theory of medicine, or the phlogiston theory of combustion. In these cases science hasn’t provided us with a more detailed account of these theories, but completely rejected them as valid scientific concepts to be replaced by entirely different accounts. The Churchlands argue that our common-sense concept of belief is similar, in that as we discover more about neuroscience and the brain, the inevitable conclusion will be to reject the belief hypothesis in its entirety.
• Our common-sense understanding of belief is entirely wrong, however treating people, animals and even computers as if they had beliefs, is often a successful strategy - The major proponents of this view, Daniel Dennett and Lynne Rudder Baker, are both eliminativists in that they believe that beliefs are not a scientifically valid concept, but they don’t go as far as rejecting the concept of belief as a predictive device. Baker gives the example of playing a computer at chess. While few people would agree that the computer held beliefs, treating the computer as if it did (e.g. that the computer believes that taking the opposition’s queen will give it a considerable advantage) is likely to be a successful and predictive strategy. In this understanding of belief, named by Dennett the intentional stance, belief based explanations of mind and behaviour are at a different level of explanation and are not reducible to those based on fundamental neuroscience although both may be explanatory at their own level.

Delusional beliefs

See also

• delusion
• folk psychology
• Gettier problem
• Moore's paradox
• propositional attitude
• propositional knowledge
• self-deception
• belief system