This brief introductory chapter outlines the reasons for and aims of this inquiry into the nature and purpose of belief. The main problem is that belief is such a poor guide to truth, which raised the question of whether this is its function, as it is commonly supposed to be. The inquiry will lead to the conclusion that the purpose of belief is to be a guide to practical action.

This chapter describes and comments on mistaken beliefs that are or have been orthodox or at least common in whole communities. So-called culture-bound psychoses are illustrated by shen-k'uei in Taiwanese culture and malgri among natives of Mornington Island. So-called epidemic hysteria is illustrated by an outbreak of witchcraft in Christian Europe, the epidemic of shell shock among allied soldiers in the First World War, and the epidemic of RSI in Australia from 1980 to 1986. Brief notes on myths, legends, rumours, and conspiracy theories complete the chapter.

This chapter analyses the four main theories of belief in some detail. These are the intellectualistic theory that belief is a cognitive act related to evidence that the thing believed is probably true, the dispositional theory that we recognize our own beliefs by observing how we react to things, the feeling theory that belief is a particular feeling that comes to us and is a signal to us that we believe or think to be true the thing under consideration, and eliminativist theories that belief does not exist, but is an illusion of our language and culture. The strengths and weaknesses of each theory are examined. The main weaknesses of the intellectualistic theory are the high frequency of irrational beliefs and beliefs the believer cannot justify with evidence, the speed and ease of belief, the inability to withhold judgement, and the largely involuntary nature of belief. The attempts that have been made to overcome these difficulties are considered. The main weaknesses of the feeling theory are that some people report that they are not aware of feelings of belief, that the theory makes use of subjective experience and introspection, that beliefs have duration and can continue beyond the brief time they are felt in consciousness, and the existence of what are called tacit or unconscious beliefs. The attempts that have been made to overcome these difficulties, including my own contribution, are considered. The balance of evidence seems to favour the feeling theory, and this theory is adopted.

The evolution of the nervous system is described, with speculation on when consciousness first appears and when belief first appears. The developments of nonverbal communication and flexibility of response are traced. With humans the ability for mental simulation and inquiry by thought experiments appears, greatly extending the old method of trial by error. Humans still do most of the old things in the old ways, nonverbal communication, emotional feeling and expression, trial and error, family and kinship, in-group behaviour, aggression, conditioned behaviour, and instinct. System 2 reasoning has evolved, while old system 1 reasoning, of which belief is a part, retains its importance. The unique ability to adapt the environment to suit human needs has evolved.

The things that lead people to form beliefs are described. Among the factors discussed are the difficulties in using evidence well, the failure to withhold judgement, vacillating belief, the unconscious biases in reasoning, the tendency to wishful believing, the reluctance to change prior beliefs, the influence of shared beliefs of a community or group, the contrast between direct experience and testimony, how language is used, the effects of repetition and propaganda, personality, ego defence mechanisms, mood and emotion, mystical thinking, revelation, and natural credulity. A section on intelligence explains how high intelligence gives poor protection from holding foolish beliefs, with examples of mistaken beliefs of gifted people.

A brief section on consciousness describes the different definitions the term has had, discusses the vexed issues of qualia, subjective experience, or mental events, and the explanatory gap, and announces the intention to take consciousness for granted and get on with the inquiry into the nature of belief. Attention is considered more fully, because it determines what we notice, which affects what we believe. There is deliberate attention and automatic attention, and a centre and periphery of attention. The factors that attract and terminate attention are discussed and illustrated.

Many beliefs depend on memories, and memories can be unreliable. This chapter deals briefly with the anatomy and physiology of memory, and defines the different kinds of memory _ long-term or declarative memory, which includes episodic or autobiographical memory, and semantic memory or memory of learned knowledge, source memory, procedural memory, working memory, and implicit, tacit or nondeclarative memory. Special attention is given to working memory and tacit memory, because they are important, and will be unfamiliar to some readers.

Introspection is necessary for knowing what conscious mental events a person has in his or her mind. This is all the feeling theory of belief asks it to do. Denying or neglecting this is one source of eliminativism. The explanations we offer for our own thoughts, emotions, preferences, choices, beliefs, desires, motives, statements, and actions, which seem to come from introspection, are unreliable. Introspection also gives us a set of potent intuitions, which include some of philosophy’s most intransigent problems — that time flows, that mind and body are dual, that mental events are immaterial, and the intuition on which this book depends, the intuition that conscious mental events cause behaviour. The chapter ends with a comment on the uniqueness of mental events, and their difference from a computer output.

The first part of the chapter discusses the nature of emotion and the new and old definitions of emotion. The reasons for working with the old or feeling theory are that it is still the familiar theory, that it provides a unifying factor for all the otherwise very different emotions, and it allows the separation of emotion, which is considered to be a signal to the person having the emotion, from facial expression, body language, and nonverbal communication, which are considered to be signals to other people, evolved to elicit helpful responses. Emotions are found to share a number of properties with belief, this is considered to be support for the feeling theory of belief. There is comment on the ineffable nature of emotion.The second part of the chapter deals with the nature of particular emotions, and the effects they have on the beliefs of people who are under their influence.

The selective nature of perception is noted, we only notice some things. The automatic monitoring of perception by belief is noted, and the possibility of mistaken judgements of perception. How sensory stimuli are picked up by sensory organs and transferred to the brain as trains of action potentials is understood, but how the brain transcodes these similar trains to the different perceptions of sight, sound, smell, taste, touch, and pain is unknown. There are mysterious elements in how perceptions are projected from the brain to surrounding space and to other parts of the body. This projection may be a factor in the intuition of dualism. The ineffable nature of perceptions is demonstrated. The chapter ends with a note on the nature of mental imagery and its role in thought.

The chapter opens by questioning the role of personality traits in causing behaviour, and decides to work with the common assumption that they have an important role. There is an account of the search for the real units or traits of personality. Some of the traits and dispositions, selected for their particularly direct effect on belief, for example, strong need for closure, are briefly described. There is a comment on the way long-standing occupational roles can sometimes modify personality

Evolution by group selection is accepted as important in all social animals, and illustrated by examples. In-group and out-group psychology can be seen in young infants, it is an old function of the old brain, it favours the in-group and devalues outgroups, it is related to emotion, symbolism, loyalty, patriotism, honour, pride, aggression, sacrifice, and war. It is involved in personal identity, sense of self, and pride of place. It determines many beliefs.

Symbols are things that people (or animals) have learned refer to or stand for something else. They are the basis of nonverbal communication in animals. Humans use symbols that relate to in-group psychology, loyalty, power, and remembrance. Such symbols often have a strong emotional charge, and may lead to overvalued or mistaken beliefs and magical thinking. Graves, flags, and the Christian Eucharist are examples. Some symbols are private and personal. Some symbols are unrecognized and exert their influence through unconscious processes. Other human symbols relate to the new function of language and do not have the same emotional power. Some evidence is presented that symbols work by an ‘as if’ mechanism, using some of the same neural circuits that the thing symbolized uses. People can think in symbols, for example, a sentence can use the word dog without either the speaker or the listener having a mental image of a dog.

The chapter begins with a discussion of names, descriptive names, and definitive descriptions, with the suggestion that a description becomes a descriptive name, and later simply a name, as it becomes a symbol for the thing it refers to. The issue of naming the several categories of things that we cannot describe accurately is raised. This includes a look at Wittgenstein´s private language argument. The problems of universals, nominalism, and realism are explained and commented on. The influence these issues can have on belief is illustrated with the debate on whether delusions are beliefs, and the issue of moral relativism is raised. The chapter ends with brief comment on misunderstanding through slippage of meaning, and on the Whorf-Sapir hypothesis.

This chapter deals with the role belief plays in inquiry. Inquiry begins by belief that there is a problem and is terminated by belief that a solution is found or cannot be found. It is the beliefs that count, not the truth of the matter. The process is subject to some voluntary control but in most applications it is automatic. This function of belief was described long ago by C. S. Peirce, but has since received little attention. It gives speed and economy to inquiry, with some sacrifice of accuracy for speed, and is relevant to the purpose of belief.

There are difficulties for forming sound beliefs about complex subjects. The evidence about them is often complex, and subject to misinformation, and the beliefs formed about them are often too simple and wishful. The beliefs of young children are fallible in all the usual ways. Some ideas come naturally to children and seem to be evolved adaptations. These may be the sources of the paranormal beliefs that are common among adults. Some parts of the brain are active during dreaming sleep and other functions are inactive. Disbelief is inactive, and the loss of its restraining effect on chains of association of ideas may be why absurdities arise and are accepted.

People with frontal lobe damage often have few and poor beliefs. An important part of the cause of this is their loss of ability for counterfactual thinking. Occasionally a patient with epilepsy arising in the medial temporal lobe reports abnormally intense belief that is free-floating and attaches to everything in consciousness. A similar intense belief sometimes occurs under the influence of mindaltering drugs, and during supreme athletic moments. Odd effects on belief occur in neurological neglect syndromes, and after surgical section of the corpus callosum. There are striking effects on belief in some patients with mental illness, including depression, obsessional hypochondriasis, and obsessive-compulsive disorder. Schizophrenia impinges on belief in several ways. Delusions, reality testing, and empathy are examined, and the possibility that belief is unnaturally intense in some sufferers is raised.

The nature of belief is considered to be a specific faint feeling that is a signal to the person that he or she is believing the item under consideration. Disbelief is a different specific feeling that is a signal to the person that the item is disbelieved. The purpose of belief is to be one of the important guides to practical action. Belief provides a direct prompt to action, and, by its regulation of inquiry, gives speed and economy to reaching decisions. Good and prompt practical action is important for evolutionary fitness. When the criterion of indicating truth is discarded and the criterion of guiding action is adopted many of the puzzling observations about belief fall into place, including the existence of mistaken beliefs and of personally unverified beliefs, the biases of reasoning, the inability to withhold judgement, and the existence of vacillating beliefs. Belief also serves the human need to belong to a group that has a shared set of beliefs about values. The second part of the chapter is a brief personal note on the history of my interest in belief, and a reassessment of two of my own contentious beliefs. The chapter ends with notes on two old philosophical questions: the relations between belief, knowledge, and opinion; and theories of truth. These are looked at from the perspective of the feeling theory of belief.

Conscience depends on beliefs about values. The point of the chapter is that conscience is fallible, being based on fallible beliefs, though some people sometimes regard conscience as infallible. The chapter examines the implications of this, without really solving the dilemma.

The final chapter is on the question of immaterial mind, the ghost in the machine. Some time is spent on Cartesian dualism, partly because Descartes is often misquoted and misunderstood, but all the main views are examined, without reaching a definite conclusion. I believe we do not know, we only have beliefs about this, and our beliefs depend on where our faith lies. The book ends by giving some of the implications that I believe follow from this uncertainty.