I'm about half-way through this fascinating book, conveniently available for free online, which is at the intersection of psychiatry and evolutionary psychology. I don't have the time to do it justice, so I'm going to post a few choice excerpts here in the hope that those who are more prolific and insightful than I am will add further analysis.

Just to make sure it's clear how this all ties in to bias, I'll start with a bias-relevant section. The book ties delusional behavior in with the theory of consciousness as primarily existing for social intelligence purposes, and thus malfunctions in our reading of the social facts such as human intention are what cause delusions:

But some people with delusions are entirely ‘normal’ except for the false belief, and the belief itself is neither impossible nor outlandish. Any other unusual behaviors can be traced back to that false belief. For instance, a man may have the fixed, false and dominating belief that his wife is having an affair with a neighbour. This belief may be so dominating as to lead to a large program of surveillance - spying on his wife, searching her handbag, examining her clothes etc. Yet the same man may show no evidence of irrationality in other areas of his life, being able to function normally at work and socializing easily with acquaintances, so that only close friends and family are aware of the existence of the delusion. In such instances the delusion is said to be ‘encapsulated’, ie. sealed-off from other aspects of mental life, and these people are said to have a delusional disorder.

...

Delusions are typically stated to have three major defining characteristics. Firstly that a delusional belief is false, secondly that this false belief is behaviorally dominant, and thirdly that the false belief is resistant to counter-argument. All these characteristics are shown by delusional disorders, yet they occur in a context of generally non-pathological cognitive functioning.

Humans are extremely prone to ‘false’ beliefs, or at least beliefs that strike many or most other people as false. Some of these false beliefs are strongly held and dominate behavior. It is trivially obvious that humans are imperfect logicians operating for most of the time on incomplete information, so mistakes are inevitable. But it is striking that although everyone would acknowledge the imperfections of human reasoning, many of these false beliefs are not susceptible to argument. For example, deeply cherished religious and political beliefs are nonetheless based on little or no hard evidence, vary widely, yet may dominate a person’s life, and are sometimes held with unshakeable intensity. And religious and political beliefs may strike the vast majority of other people as obviously false.

...

On reflection, we all harbor beliefs that may strike other people as false, even abhorrent, yet they could not persuade us out of them, at least not over a short timescale. Deeply felt beliefs do sometimes change over a lifetime but not necessarily as a consequence of compelling evidence - people sometimes change their political views, convert to a new religion or to agnosticism, and in their personal lives go through several revisions of their opinion about who is the most beautiful and desirable woman/ man in the world.

In other words, delusions are a part of everyday life - but all these everyday delusions are of a particular sort. They are all delusions in relation to social intelligence. At root, all these false, or at least unjustifiable, beliefs are based upon interpretations of the human world. Even some of the more strange beliefs people have about cosmology and metaphysics often boil down to beliefs about agency - the power and influence of powerful and influential agents - whether human or supernatural.

The book is hosted on HedWeb, and you can see why - it has a DIY transhumanism ethos that is happy to leap from diagnosis to ideas about treatment:

Psychiatry and the Human Condition provides an optimistic vision of a superior alternative approach to psychiatric illness and its treatment, drawing upon modern neuroscience and evolutionary theory. Psychiatric signs and symptoms - such as anxiety, insomnia, malaise, fatigue - are part of life for most people, for much of the time. This is the human condition. But psychiatry has the potential to help. In particular, psychotropic drugs could enable more people to lead lives that are more creative and fulfilled. Current classifications and treatments derive from a century-old framework which now requires replacement. Available psychotropic drugs are typically being used crudely, and without sufficient attention to their psychological effects.

We can do better. This book argues that obsolete categories of diseases and drugs should be scrapped. The new framework of understanding implies that clinical management should focus on the treatment of biologically-valid symptoms and signs, and include a much larger role for self-treatment.

It discusses the economics of hunter-gatherer societies, which provides a clue about several biases:

Most people’s ideas of ‘primitive’ or ‘tribal’ life is based on agricultural or herding modes of production. In such societies there is invariably domination of the mass of people by a ‘chief’ (plus henchmen) who appropriate a large share of resources. But in an ‘immediate return’ or ‘simple hunter-gatherer’ economy there is an extremely egalitarian social system, with very little in the way of wealth differentials. Food is gathered on a roughly daily basis for rapid consumption, and tools or other artifacts were made as required. There was no surplus of food or material goods, no significant storage of accumulated food or other resources, and the constraints of nomadic life meant that artifacts can not be accumulated.

One of the most distinctive features of foraging societies, as contrasted with human societies that currently exist, was that ancestral societies were to a high degree egalitarian and without significant or sustained differentials in resources among men of the same age. There were indeed differentials in resource allocation according to age and sex (eg. adults ate more than children, men ate more than women) - but there was not a class or caste system, society was not stratified into rich and poor people who tended to pass their condition on to their children.

This equality of outcome is achieved in immediate-return economies by a continual process of redistribution through the sharing of food on a daily basis, and through continual equalizing redistribution of other goods. The sharing may be accomplished in various ways in different societies, including gambling games of chance or the continual circulation of artifacts as gifts. But the important common feature is that sharing is enforced by a powerful egalitarian ethos which acts to prevent a concentration of power in few hands, and in which participants are ‘vigilant’ in favour of making sure that no-one else takes more than themselves. If each individual person ensures that no-one else gets more than they do, the outcome is equality.

You can see here the roots of pessimisstic bias (the belief that material wealth is increasing far more slowly than it is), since in the HG society, there was no ability to leverage capital to exponentially grow wealth over time. Also, this means no intuitive understanding of how small differences in personal or national productivity can lead over time to huge differences in wealth. The progressive passion for equality through redistribution and their blind spot about the growth-choking effect of these policies makes sense too - in the HG environment, there was no capital growth, so redistribution didn't choke growth, it just helped everyone stay fed. Suspicion of the very wealthy makes sense, because there was no way for a HG to become very wealthy, as there was no storage of important resources.

Of the three kinds of society as described by Gellner: hunter-gatherer, agrarian, and mercantile, it is probable that hunter-gatherers had the best life, overall. Hunter gatherer societies are the happiest and peasant societies are the most miserable - while industrial-mercantile societies such as our own lie somewhere in between.

That, at any rate, is the conclusion of anthropologist Jerome Barkow - and his opinion is widely confirmed by the reports of many independent anthropologists who have experienced the alternatives of foraging, agrarian and industrial society...

Another line of evidence is patterns of voluntary migration. When industrial mercantile societies develop, they are popular with the miserable peasantry of agrarian societies who flee the land and crowd the cities, if given the chance. Not so the happier hunter gatherers who typically must be coerced into joining industrial life. My great grandparents left their lives as rural peasants and converged from hundreds of miles and several countries to work the coal mines of Northumberland. They swapped the open sky, fields and trees for a life underground and inhabiting dingy rows of colliery houses. Being a miner in the early twentieth century must have been grim, but apparently it was not so bad as being an agricultural laborer.

My hypothesis is that when most people think about people in the third world moving to factory jobs, they model the current state of those people as happy hunter-gatherers. Our idealized vision of the happy past is our instinct about happy hunter-gatherers applied incorrectly to agrarian societies. In practice, there are very few hunter-gatherers left, and the reason people go to sweatshop jobs is because those jobs are far better than the miserable toil of subsistence farming.

(Which rather begs the question of why people move to subsistence farming. Perhaps it's a group selection thing - agrarian societies are so much more productive (they accumulate capital, albeit slowly, and can support much larger population bases which means more ideas and gains from trade) that those who choose them outcompete those who don't.)

It then moves on to meatier psychiatric topics, like the crapitude of the current taxonomy for psychiatric disorders:

These diagnostic systems employ a syndromal system of classification that derives ultimately from the work of the psychiatrist Emil Kraepelin about a hundred years ago, and is therefore termed the ‘neo-Kraeplinian’ nosology. Whether or not a psychiatrist uses the formal diagnostic criteria, the neo-Kraeplinian nosology has now become ossified in the DSM and ICD manuals. Over the past few decades the mass of published commentary and research based on this nosology has created a climate of opinion to challenge which is seen as not so much mistaken as absurd.

Yet the prevailing neo-Kraeplinian nosology is a mish-mash of syndromes that have widely varying plausibility and coherence. Some diagnoses are probably indeed biologically valid - having perhaps a single cause, occurring in a single psychological functional system, or having a unified pathology (some of the anxiety disorders, for instance, such as generalized anxiety, panic and simple phobias) But from the perspective of providing a sound basis for scientific research, especially for the core diagnoses of the ‘functional psychoses’, the whole thing is a terrible, misleading mess.

It might be thought that the current diagnostic schemes are supported by a wealth of scientific research. But almost the opposite is the case. Despite widespread skepticism in the research literature about the validity of the current diagnostic categories, it is still the case that almost all biological research is based upon neo-Kraeplinian diagnoses, them rather than neo-Kraeplinian diagnoses being based on research.

There is lots more to be read and said, hopefully this has piqued your interest.