Chapter 9                               The Practical Criticism of Bayesianism

 

In the first place, say its critics, Bayesianism simply can’t be an accurate model of how humans think because humans violate the Bayesian model every day. Every day, we commit acts that are at odds with what both reasoning and experience have shown is rational. Some nations still execute murderers. Some men continue to bully and exploit women. Some adults still spank children. Too many of us still fear people who look different from us on no other grounds than that they look different from us. We shun them even when we have evidence showing there are many trustworthy individuals in that other group and many untrustworthy ones in the group of people who associate with us. We do these things even when experimental evidence and everyday experience both indicate such behaviors are counterproductive. That is the opposite of Bayesianism.

Over and over, we act in ways that are illogical by Bayesian standards. We too often stake the best of our human and material resources on ways of behaving that both reasoning and evidence say do not work. Can Bayesianism account for these glaring bits of evidence that are inconsistent with its model of thinking?

The answer to this critique is disturbing. The problem is not that the Bayesian model doesn’t work as an explanation of human thinking and behavior. The problem is rather that the Bayesian model of human thinking and behavior works too well. The irrational, un-Bayesian behaviors individuals engage in are not proof of Bayesianism’s inadequacy, but rather parts of a larger proof of how it applies to the thinking, learning, behavior, and evolution not just of individual humans, but of whole communities and even whole tribes and nations.

Societies continually evolve and change because every society contains at least a few people who are naturally curious. Curious people constantly imagine and test new ideas and new ways of doing things like working, getting food, raising kids, fighting off invaders, healing the sick – any of the things the society must do in order to carry on. Often, subgroups in society view any new concept or way of doing things as threatening to their most deeply held beliefs. However, if adherents of the new idea keep demonstrating that their idea works better – gets more work done, saves more lives, nurtures better-adjusted infants into citizens, etc. – than does currently common practice, then the larger society usually marginalizes the less effectual citizens and their ideas and adopts the new way of farming, building shelters, healing the sick, etc.

In this way, a society mirrors what an individual does when he finds a better way of growing corn or teaching kids or easing Grampa’s arthritic pain. In this way, we adapt – as individuals, but more profoundly, as societies – to changes in our environments, and to new lands and markets and new technologies such as plows, vaccinations, cars, televisions, computers, and so on. Farmers, carpenters, teachers, doctors, etc. who cling to obsolete ways are passed by, often even by their own children or grandchildren.

But then there are the more disturbing cases, the ones that caused me to write in my last chapter that we are almost completely devoid of any unshakable beliefs. Sometimes large minorities or even majorities of citizens do hang on to obsolete concepts and ways, in spite of mounds of evidence which say those ideas don’t work as well in current circumstances as the new ones others are using.

The Bayesian model of human thinking works well, most of the time, to explain how individuals form and evolve their basic idea systems. Most of the time, the model also can explain how a whole community, tribe, or nation can grow and change its sets of beliefs, customs, and practices. But can it account for the times when majorities in a society do not embrace a new, more effective model, in spite of Bayesian observations and calculations showing the idea is sound and useful? In short, can the Bayesian model explain the biases that we see in the dark side of reactionary tribalism, the kind of thinking that works to return a society to the beliefs and customs of its past?

          Nazi party rally, 1934. Tribalism at its worst (credit: Wikimedia Commons)

As we saw in our last chapter, for the most part, individuals become willing to drop a set of ideas that seems to be losing its effectiveness when they encounter a new set of ideas that looks more promising. They embrace the new ideas that perform well, that more effectively guide the individual, the family, even their whole society, through the challenges and hazards of surviving in the physical world.

At the tribal level, whole societies usually drop models of reality, and the ways of thinking and living based on those models, when citizens repeatedly see that a set of new ideas is getting better results. When your neighbors are producing bigger crops, you want to know how and why, and you want to use the new practices that work. When the plague comes, you’ll do whatever works to keep yourself and your loved ones from getting it.

Sometimes, on the level of social change, this mechanism can cause societies to marginalize or ostracize subcultures that refuse to let go of the old ways. Cars and "car people" marginalized the horse culture within a generation. Assembly line factories brought the unit cost of goods down until millions who had once thought that they would never have a car, an icebox, or a TV bought one on credit and took it home. When assembly line factories came in, old, small-scale shops where teams of men made cars one at a time were obsolete.

The point is that when a new subculture with new beliefs and ways keeps getting good results, and the old subculture keeps proving less effectual by comparison, the majority usually do make the switch to the new way – of chipping flint, growing corn, spearing fish, making arrows, weaving cloth, building ships, forging gun barrels, dispersing capital to the enterprises with the best growth potential, or connecting a computer to the worldwide net.

It is also important to note here that, for most new practices, tests applied to them only confirm that the old way is still better. Most new ideas are tested and found to be less effective than the established ones. Only rarely does a more effective one come along. But the crucial insight into why humans sometimes do very un-Bayesian things is the one that comes next.

Sometimes, if a new paradigm – i.e. the worldview that underlies a new practice – challenges a tribe’s core beliefs, Bayesian calculations about what a society will do next fail. Sometimes tribes continue to adhere to obsolete beliefs. The larger question here is whether the Bayesian model of human thinking, when taken up to the level of human social/cultural evolution, can account for these apparently un-Bayesian choices and actions on the parts of individuals and their tribes.

Our most deeply held beliefs are those that guide our interactions with other people – family, friends, neighbors, colleagues, fellow citizens, and foreigners. These are the parts of our lives that we usually see as being guided not by reason, but by deep moral beliefs – beliefs grounded in sources much more profound than our beliefs about the sensory world. In anthropological terms, these are the beliefs that enable the members of the tribe to achieve social solidarity – to live together, interact, achieve teamwork, and get along as a tribal team.

The continued exploitation of women and execution of murderers described above are both irrational, but are both consequences of the fact that, in spite of our worries about the failures of our moral code in the last hundred years, much of that code lingers on. In many aspects of our lives, we are still drifting with our traditional ways, even though our confidence in those ways is eroding steadily. We don’t know what else to do. In the meantime, these traditional ways are so deeply ingrained and familiar as to seem to us to be “natural”, in spite of mounds of evidence showing that they are counterproductive.

When we study the deepest and most profound of these “traditional” beliefs, we are dealing with those beliefs that are most powerfully programmed into every growing child by nearly all of his tribe’s adult members. These beliefs don’t obey the Bayesian models that usually govern the learning processes of the individual. In fact, they’re almost always viewed by the individual as being the most crucial parts of his tribe and himself. They are guarded in the mind by programmed emotions of fear and anger. We get scared and mad when we think our values are being threatened. They are the beliefs that our parents, teachers, storytellers, and leaders enjoin us to hang on to at all costs. In fact, for most people in most societies, these beliefs and the morés that grow from them are considered “normal”. Varying from them is viewed as “abnormal”.

For centuries, in the West our moral meta-belief – that is to say, our belief about our moral beliefs – was that they had been set down by God and, thus, were universal and eternal. When we took that view, we were in effect placing our moral beliefs in a separate category from the rest, a category meant to guarantee their immutability. Non-Western societies do parallel things. 

 

 

     

                                  

                                  John Stuart Mill (credit: Wikimedia Commons)

 

But are our moral beliefs really different from our beliefs in areas like Science, athletics, farming, cooking, or automotive mechanics? 

The answer is “yes and no”. We are eager to learn better farming practices and medical therapies, and to win at track meets. But, in their attitudes about the executing of our worst criminals or the exploitation of women, many in our society are slow to change. Historical evidence shows societies can change in these areas, but only grudgingly. (J.S. Mill, a nineteenth-century British philosopher, discussed the obstinacy of old ways of thinking about women, for example, in the introduction to his essay, The Subjection of Women.¹)

So, can these core beliefs – our values – still be understood in a Bayesian way? Yes. But in a very harsh way. Sometimes, the moral beliefs that humans hold most deeply only get changed in an entire nation when experience proves by pain that the old values no longer work, i.e. when the values begin to fail as guidelines by which the humans who hold them can effectively make choices, act, and live their lives. In extreme cases, values fail so totally that the people who hold old values begin to die out. They starve or become ill or fail to reproduce or fail to program their values into their young. Or the whole tribe may even get overrun. By one of these mechanisms, a tribe’s entire culture can die out. The tribe’s genes go on in children born from the merging of two tribes, but most of the losing tribe’s culture becomes a footnote in history.

And so it is that, as the critics of Bayesianism point out, humans of past societies often behaved in ways that seem irrational by Bayesian standards. (One of the main aims of this book is to try to provide a way of thinking that makes deep change doable and in fact so readily doable that a society can change its values without thousands, or even millions, of its people getting killed.)

Even in our time, some adults still spank kids. Some men still bully women. Some states still execute murderers. Research on these morés says they don’t work; these behaviors do not achieve the results they aim for. In fact, these patterns of behavior and the beliefs underlying them exactly fit the term counterproductive. States that execute killers have higher murder rates.

Why do we sometimes act irrationally? Because our culture’s institutions – the family, the schools, and the media – continue to indoctrinate us with these values so deeply that once we are adults, we refuse to examine them. Instead, our cultural programming causes us to bristle, and then to defend our “good old ways”. Violently if need be. If the ensuing lessons are harsh enough, and there is a reasonable amount of time available, a society can sometimes learn, change, and adapt. But deep social change is difficult. Alfred Whitehead, in 1927, wrote: “The major advances in civilization are processes which all but wreck the societies in which they occur”.^2.

  

             

                                Lethal injection room, used to execute criminals  

                                               (credit: Wikimedia Commons)                           

                    

                           Alfred North Whitehead      (credit: goodreads.com) 

 

 

It is also worthwhile to say the obvious here, however politically incorrect it may be: all our obsolete-obstinate beliefs, values, and behavior patterns did serve useful ends at one time. That is why we acquired them in the first place. 

For example, in some early societies, women were taught to be submissive, first to their fathers and brothers, then their husbands. The majority of men in such societies were thus more likely to help to nurture the children of their socially sanctioned marriages because each man was confident the children born to “his” woman (or women) were biologically his.

Raising kids is hard work. It requires constant attention to reams of hazards. In early societies, if both parents were committed to the task, the odds were better that those children would grow up, marry, have kids of their own, and then program into those kids the values and roles that their parents had been raised to believe in. Non-patriarchal societies taught other roles for men and women and other designs for the family, but they weren’t as prolific as patriarchy over the long haul.

Patriarchy isn’t fair. But it makes lots of babies who become adult citizens. Workers. Soldiers. Lots of them. This view of patriarchy is harsh, but real.

Patriarchy’s beliefs about male and female roles didn’t work to make people happy. But they did give some tribes numbers and power. They are obsolete today, partly because child nurturing has been largely taken over by the state (public schools), partly because no society in a post-industrial, knowledge-driven economy can afford to stifle half its human resources (i.e. the female half), and partly because there are too many humans polluting the Earth now. 

Population growth is no longer a wise goal because it no longer brings a nation power. In today’s world, millions of poor are likely to be a liability, not an asset, for a nation. They don’t produce goods and services at anything like the rates of more skilled workers in developed societies. If they suffer too much, they might even start a violent revolution and unravel their own way of life, i.e. destroy the old order.