WHAT SCIENTIFIC CONCEPT WOULD IMPROVE EVERYBODY'S COGNITIVE TOOLKIT?
Psychologist, UPenn; Director, Penn Laboratory for Experimental Evolutionary Psychology (PLEEP); Author, Why Everyone (Else) is a Hypocrite
When I go about doing what I do, frequently I affect you as an incidental side effect. In many such cases, I don't have to pay you to compensate for any inadvertent harm done; symmetrically, you frequently don't have to pay me for any inadvertent benefits I've bestowed upon you. The term — externalities — refers to these cases, and they are pervasive and important because, especially in the modern, interconnected world, when I go about pursuing my own goals, I wind up affecting you in any number of different ways.
Externalities can be small or large, negative and positive. When I lived in Santa Barbara, many people with no goal other than working on their tans generated (small, true) positive externalities for passersby, who benefitted from the enhanced scenery. These onlookers didn't have to pay for this improvement to the landscape but, on the same beach, rollerbladers, traveling at high speed and distracted by this particular positive externality, occasionally produced a negative one in the form of a risk of collision for pedestrians trying to enjoy the footpath.
Externalities loom large in the present era, when actions in one place can potentially affect others half a world away. When I manufacture widgets for you to buy, to make them I might, as a side effect of the process, produce waste that makes the people around my factory — and maybe around the world — worse off. As long as I don't have to compensate anyone for polluting their water and air, it's unlikely I'll make much of an effort to stop doing it.
At a smaller, more personal scale, we all impose externalities on one another as we go through our daily lives. I drive to work, increasing the amount of traffic you face. You feel the strange compulsion that infects people in theaters these days to check your text messages on your cell phone during the film, and the bright glow peeking over your shoulder reduces my enjoyment of the movie.
The concept of externalities is useful because it directs our attention to unintended side effects. If you weren't focused on externalities, you might think that the way to reduce traffic congestion was to build more roads. That might work, but another way, and a potentially more efficient way, is to implement policies that force drivers to pay the cost of their negative externalities by charging a price to use roads, particularly at peak times. Congestion charges, such as those implemented in London and Singapore, are designed to do exactly this. If I have to pay to go into town during rush hour, I might stay home unless my need is pressing.
Keeping externalities firmly in mind also reminds us to be vigilant about the fact that in complex, integrated systems, simple interventions designed to bring about a particular desirable effect will potentially have many more consequences, both positive and negative. Consider, as an example, the history of DDT. When first used, it had its intended effect, which was to reduce the spread of malaria through the control of mosquito populations. However, its use also had two unintended consequences. First, it poisoned a number of animals (including humans) and, second, it selected for resistance among mosquitoes. Subsequently, policies to reduce the use of DDT probably were effective in their goals of preventing these two negative consequences. However, while there is some debate about the details, these policies might themselves have had an important side effect, increasing rates of malaria, carried by the mosquitoes no longer suppressed by DDT.
The key point is that the notion of externalities forces us to think about unintended (positive and negative) effects of actions, an issue that looms larger as the world gets smaller. It highlights the need to balance not only the intended costs and benefits of a given candidate policy, but also the unintended effects of the policy. Further, it helps focus attention on one type of solution to the problems of unintended harms, which is to think about using prices to provide incentives for people and firms to produce more positive externalities and fewer negative ones.
Considering externalities in our daily lives directs our attention to ways in which we harm, albeit inadvertently, the other people around us, and can be used to guide our own decision making, including waiting until after the credits have rolled to check our messages.
DAVID G. MYERS
Social psychologist, Hope College; Author, A Friendly Letter to Skeptics and Atheists
Most of us have a good reputation with ourselves. That's the gist of a sometimes amusing and frequently perilous phenomenon that social psychologists call self-serving bias.
Accepting more responsibility for success than failure, for good deeds than bad.
In experiments, people readily accept credit when told they have succeeded (attributing such to their ability and effort). Yet they attribute failure to external factors such as bad luck or the problem's "impossibility." When we win at Scrabble it's because of our verbal dexterity. When we lose it's because "I was stuck with a Q but no U."
Self-serving attributions have been observed with athletes (after victory or defeat), students (after high or low exam grades), drivers (after accidents), and managers (after profits and losses). The question, "What have I done to deserve this?" is one we ask of our troubles, not our successes.
The better-than-average phenomenon: How do I love me? Let me count the ways.
It's not just in Lake Wobegon that all the children are above average. In one College Board survey of 829,000 high school seniors, zero percent rated themselves below average in "ability to get along with others," 60 percent rated themselves in the top 10 percent, and 25 percent rated themselves in the top 1 percent. Compared to our average peer, most of us fancy ourselves as more intelligent, better looking, less prejudiced, more ethical, healthier, and likely to live longer — a phenomenon recognized in Freud's joke about the man who told his wife, "If one of us should die, I shall move to Paris."
In everyday life, more than 9 in 10 drivers are above average drivers, or so they presume. In surveys of college faculty, 90 percent or more have rated themselves as superior to their average colleague (which naturally leads to some envy and disgruntlement when one's talents are underappreciated). When husbands and wives estimate what percent of the housework they contribute, or when work team members estimate their contributions, their self-estimates routinely sum to more than 100 percent.
Studies of self-serving bias and its cousins — illusory optimism, self-justification, and ingroup bias — remind us of what literature and religion have taught: pride often goes before a fall. Perceiving ourselves and our groups favorably protects us against depression, buffers stress, and sustains our hopes. But it does so at the cost of marital discord, bargaining impasses, condescending prejudice, national hubris, and war. Being mindful of self-serving bias beckons us not to false modesty, but to a humility that affirms our genuine talents and virtues, and likewise those of others.
Classicist; Provost, Georgetown University; Author, The Ruin of the Roman Empire
Everything Is In Motion
Nothing is more wonderful about human beings than their ability to abstract, infer, calculate, and produce rules, algorithms, and tables that enable them to work marvels. We are the only species that could even imagine taking on mother nature in a fight for control of the world. We may well lose that fight, but it's an amazing spectacle nonetheless.
But nothing is less wonderful about human beings than their ability to refuse to learn from their own discoveries. The edge to the Edge question this year is the implication that we are brilliant and stupid at the same time, capable of inventing wonders and still capable of forgetting what we've done and blundering stupidly on. Our poor cognitive toolkits are always missing a screwdriver when we need it and we're always trying to get a bolt off that wheel with our teeth when a perfectly serviceable wrench is in the kit over there unused.
So as classicist, I'll make my pitch for what is arguably the oldest of our "SHA" concepts, the one that goes back to the senior pre-Socratic philosopher, Heraclitus."You can't step in the same river twice," he said; putting it another way his mantra was "Everything flows." Remembering that everything is in motion — feverish, ceaseless, unbelievably rapid motion — is always hard for us. Vast galaxies dash apart at speeds that seem faster than is physically possible, while the subatomic particles of which we are composed beggar our ability to comprehend large numbers when we try to understand their motion — and at the same time, I lie here, sluglike, inert, trying to muster the energy to change channels, convinced that one day is just like another, reflecting on the deep truth that my idiot cousin will never change, and wondering why my favorite cupcake store has lost its magic touch.
Because we think and move at human scale in time and space, we can deceive ourselves. Pre-Copernican astronomies depended on the self-evident fact that the "fixed stars" orbited around the other in a slow annual dance; and it was an advance in science to declare that "atoms" (in Greek, literally "indivisibles") were the changeless building blocks of matter — until we split them. Edward Gibbon could be puzzled by the fall of the Roman Empire without realizing that its most amazing feature was that it lasted so long. Scientists discover magic disease-fighting compounds only to find that the disease changes faster than they can keep up.
Take it from Heraclitus and put it in your toolkit: change is the law, stability and consistency are illusions, temporary in any case, a heroic achievement of human will and persistence at best. When we want things to stay the same, we'll always wind up playing catch-up. Better to go with the flow.
DOUGLAS T. KENRICK
Professor of Psychology, Arizona State University; Author, Sex, Murder, and the Meaning of Life; Editor, Evolution and Social Psychology
Subselves and the Modular Mind
Although it seems obvious that there is a single "you" inside your head, research from several subdisciplines of psychology suggests that this is an illusion. The "you" who makes a seemingly rational and "self-interested" decision to discontinue a relationship with a friend who fails to return your phone calls, borrows thousands of dollars he doesn't pay back, and lets you pick up the tab in the restaurant is not the same "you" who makes very different calculations about a son, about a lover, or about a business partner.
Three decades ago cognitive scientist Colin Martindale advanced the idea that each of us has several subselves, and he connected his idea to emerging ideas in cognitive science. Central to Martindale's thesis were a few fairly simple ideas, such as selective attention, lateral inhibition, state-dependent memory, and cognitive dissociation. Although all the neurons in our brains are firing all the time, we'd never be able to put one foot in front of the other if we were unable to consciously ignore almost all of that hyperabundant parallel processing going on in the background. When you walk down the street there are thousands of stimuli to stimulate your already overtaxed brain — hundreds of different people of different ages with different accents, different hair colors, different clothes, different ways of walking and gesturing, not to mention all the flashing advertisements, curbs to avoid tripping over, and automobiles running yellow lights as you try to cross at the intersection. Hence, attention is highly selective. The nervous system accomplishes some of that selectiveness by relying on the powerful principle of lateral inhibition — in which one group of neurons suppresses the activity of other neurons that might interfere with an important message getting up to the next level of processing. In the eye, lateral inhibition helps us notice potentially dangerous holes in the ground, as the retinal cells stimulated by light areas send messages suppressing the activity of neighboring neurons, producing a perceived bump in brightness and valley of darkness near any edge. Several of these local "edge detector" style mechanisms combine at a higher level to produce "shape detectors" — allowing us to discriminate a "b" from a "d" and a "p." Higher up in the nervous system, several shape detectors combine to allow us to discriminate words, and at a higher level, to discriminate sentences, and at a still higher level, place those sentences in context (thereby discriminating whether the statement "Hi, how are you today?" is a romantic pass or a prelude to a sales pitch).
State dependent memory helps sort out all that incoming information for later use, by categorizing new info according to context — if you learn a stranger's name after drinking a doppio espresso at the local java house, it will be easier to remember that name if you meet again at Starbucks than if the next encounter is at a local pub after a martini. For several months after I returned from Italy, I would start speaking Italian and making expansive hand gestures every time I drank a glass of wine.
At the highest level, Martindale argued that all of those processes of inhibition and dissociation lead us to suffer from an everyday version of dissociative disorder. In other words, we all have a number of executive subselves, and the only way we manage to accomplish anything in life is to allow only one subself to take the conscious driver's seat at any given time.
Martindale developed his notion of executive subselves before modern evolutionary approaches to psychology had become prominent, but the idea becomes especially powerful if you combine Martindale's cognitive model with the idea of functional modularity. Building on findings that animals and humans use multiple — and very different — mental processes to learn different things, evolutionarily informed psychologists have suggested that there is not a single information-processing organ inside our heads, but instead multiple systems dedicated to solving different adaptive problems. Thus, instead of having a random and idiosyncratic assortment of subselves inside my head, different from the assortment inside your head, each of us has a set of functional subselves — one dedicated to getting along with our friends, one dedicated to self-protection (protecting us from the bad guys), one dedicated to winning status, another to finding mates, a distinct one for keeping mates (which is a very different set of problems, as some of us have learned), and yet another to caring for our offspring.
Thinking of the mind as composed of several functionally independent adaptive subselves helps us understand many seeming inconsistencies and irrationalities in human behavior, such as why a decision that seems "rational" when it involves one's son seems eminently irrational when it involves a friend or a lover, for example.
Applied Mathematician; Postdoctoral Research Fellow in Health Care Policy, Harvard Medical School; Research Fellow. Institute for Quantitative Social Science, Harvard University
The Copernican Principle
The scientist Nicolaus Copernicus recognized that Earth is not in any particularly privileged position in the solar system. This elegant fact can be extended to encompass a powerful idea, known as the Copernican Principle, that we are not in a special or favorable place of any sort. By looking at the world through the eyes of this principle, we can remove certain blinders and preconceptions about ourselves and re-examine our relationship with the universe.
The Copernican Principle can be used in the traditional spatial sense, providing awareness of our mediocre place in the galaxy, and our galaxy's place in the universe. We now recognize that our solar system, once thought to be the center of the galaxy, is actually in the suburban portions of the Milky Way. And the Copernican Principle helps guide our understanding of the expanding universe, allowing us to see that anywhere in the cosmos one would also view other galaxies moving away at rapid speeds, just as we see here on Earth. We are not anywhere special.
The Copernican Principle has also been extended to our temporal position by astrophysicist J. Richard Gott to help provide estimates for lifetimes of events, independent of additional information. As Gott elaborated, other than the fact that we are intelligent observers, there is no reason to believe we are in any way specially located in time. It allows us to quantify our uncertainty and recognize that we are often neither at the beginning of things, nor at the end. This allowed Gott to estimate correctly when the Berlin Wall would fall, and has even provided meaningful numbers on the lifetime of humanity.
This principle can even anchor our location within the many orders of magnitude of our world: we are far smaller than most of the cosmos, far larger than most chemistry, far slower than much that occurs at subatomic scales, and far faster than geological and evolutionary processes. Through this principle, we are compelled to study successively larger and smaller orders of magnitude of our world, because we need not assume that everything interesting is at the same scale as ourselves.
And yet, despite this regimented approach to our mediocrity, we need not have cause for despair: as far as we know, we're the only species that can actually recognize its place in the universe. The paradox of the Copernican Principle is that, by properly understanding our place, even if it be rather humbling, we can only then truly understand our surroundings. And by being able to do that, we don't seem so small or insignificant after all.
Publisher of Skeptic Magazine; Adjunct Professor, Claremont Graduate University; Author, The Believing Brain
Think Bottom Up, Not Top Down
One of the most general shorthand abstractions that if adopted would improve the cognitive toolkit of humanity is to think bottom up, not top down. Almost everything important that happens in both nature and in society happens from the bottom up, not the top down. Water is a bottom up, self-organized emergent property of hydrogen and oxygen. Life is a bottom up, self-organized emergent property of organic molecules that coalesced into protein chains through nothing more than the input of energy into the system of Earth's early environment. The complex eukaryotic cells of which we are made are themselves the product of much simpler prokaryotic cells that merged together from the bottom up in a process of symbiosis that happens naturally when genomes are merged between two organisms. Evolution itself is a bottom up process of organisms just trying to make a living and get their genes into the next generation; out of that simple process emerges the diverse array of complex life we see today.
Analogously, an economy is a self-organized bottom up emergent process of people just trying to make a living and get their genes into the next generation, and out of that simple process emerges the diverse array of products and services available to us today. Likewise, democracy is a bottom up emergent political system specifically designed to displace top down kingdoms, theocracies, and dictatorships. Economic and political systems are the result of human action, not human design.
Most people, however, see the world from the top down instead of the bottom up. The reason is that our brains evolved to find design in the world, and our experience with designed objects is that they have a designer (us) who we consider to be intelligent. So most people intuitively sense that anything in nature that looks designed must be so from the top down, not the bottom up. Bottom up reasoning is counter intuitive. This is why so many people believe that life was designed from the top down, and why so many think that economies must be designed and that countries should be ruled from the top down.
One way to get people to adopt the bottom up shorthand abstraction as a cognitive tool is to find examples that we know evolved from the bottom up and were not designed from the top down. Language is an example. No one designed English to look and sound like it does today (in which teenagers use the word "like" every sentence). From Chaucer's time forward our language has evolved from the bottom up by native speakers adopting their own nuanced styles to fit their unique lives and cultures. Likewise, the history of knowledge production has been one long trajectory from top down to bottom up. From ancient priests and medieval scholars to academic professors and university publishers, the democratization of knowledge has struggled alongside the democratization of societies to free itself from the bondage of top down control. Compare the magisterial multi-volume encyclopedias of centuries past that held sway as the final authority for reliable knowledge, now displaced by individual encyclopedists employing wiki tools and making everyone their own expert.
Which is why the Internet is the ultimate bottom up self-organized emergent property of millions of computer users exchanging data across servers, and although there are some top-down controls involved—just as there are some in mostly bottom-up economic and political systems—the strength of digital freedom derives from the fact that no one is in charge. For the past 500 years humanity has gradually but ineluctably transitioned from top down to bottom up systems, for the simple reason that both information and people want to be free.
Psychologist, Research Associate, Harvard University; Author, Alex and Me
Fixed-Action Patterns: Using The Study Of Animal Instinct As A Metaphor For Human Behavior
The concept comes from early ethologists, scientists such as Oskar Heinroth and Konrad Lorenz, who defined it as an instinctive response — usually a series of predictable behavior patterns — that would occur reliably in the presence of a specific bit of input, often called a "releaser". FAPs, as they were known, were thought to be devoid of cognitive processing. As it turned out, FAPs were not nearly as fixed as the ethologists believed, but the concept has remained as part of the historical literature, as a way of scientifically describing what in the vernacular might be called "knee-jerk responses". The concept of a FAP, despite its simplicity, might prove quite valuable as a metaphorical means to study and change human behavior.
If we look into the literature on FAPs, we see that many such instinctive responses were actually learned, based on the most elementary of signals. For example, the newly-hatched herring gull chicks' supposed FAP of hitting the red spot on its parents' beak for food was far more complex: Hailman demonstrated that what was innate was only a tendency to peck at an oscillating object in the field of view. The ability to target the beak, and the red spot on the beak, though a pattern that developed steadily and fairly quickly, was acquired experientially. Clearly, certain sensitivities must be innate, but the specifics of their development into various behavioral acts likely depend on how the organism interacts with its surroundings and what feedback it receives. The system need not, especially for humans, be simply a matter of conditioning Response R to Stimulus S, but rather of evaluating as much input as possible.
The relevance is that, if we wish to understand why as humans we often act in certain predictable ways, and particularly if there is a desire or need to change these behavioral responses, we can remember our animal heritage and look for the possible releasers that appear to stimulate our FAPs. Might the FAP actually be a response learned over time, initially with respect to something even more basic than we expect? The consequences could affect aspects of our lives from our social interactions to what we see as our quick decision-making processes in our professional lives. Given an understanding of our FAPs, and those of the other individuals with whom we interact, we — as humans with cognitive processing powers — could begin to re-think our behavior patterns.
Computational Neuroscientist, Francis Crick Professor, the Salk Institute, Coauthor, The Computational Brain
Powers of 10
An important part of my scientific toolkit is how to think about things in the world over a wide range of magnitudes and time scales. This involves first understanding powers of ten; second, visualizing data over a wide range of magnitudes on graphs using logarithmic scales; and third, appreciating the meaning of magnitude scales such as the decibel (dB) scale for the loudness of sounds and the Richter scale for the strengths of earthquakes.
This toolkit ought to be a part of everyone thinking, but sadly I have found that even well educated nonscientists are flummoxed by log scales and can only vaguely grasp the difference between an earthquake on a Richter scale of 6 and 8 (a thousand times more energy released). Thinking in powers of 10 is such a basic skill that it ought to be taught along with integers in elementary school.
Scaling laws are found throughout nature. Galileo in 1638 pointed out that large animals have disproportionately thicker leg bones than small animals to support the weight of the animal. The heavier the animal, the more stout their legs need to be. This leads to a prediction that the thickness of the leg bone should scale with the 3/2 power of the length of the bone.
Another interesting scaling law is that between the volume of the cortical white matter, corresponding to the long-distance wires between cortical areas, and the gray matter, where the computing takes place. For mammals ranging over 5 orders of magnitude in weight from a pygmy shrew to an elephant, the white matter scales as the 5/4 power of the gray matter. This means that the bigger the brain, the disproportionately larger the fraction of the volume taken up by cortical wiring used for communication compared to the computing machinery.
I am concerned that students I teach have lost the art of estimating with powers of 10. When I was a student I used a slide rule to compute, but students now use calculators. A slide rule lets you carry out a long series of multiplications and divisions by adding and subtracting the logs of numbers; but at the end you need to figure out the powers of 10 by making a rough estimate. A calculator keeps track of this for you, but if you make a mistake in keying in a number you can be off by 10 orders of magnitude, which happens to students who don't have a feeling for orders of magnitude.
A final reason why familiarity with powers of 10 would improve everyone's cognitive toolkit is that it helps us comprehend our life and the world in which we live:
How many seconds are there in a lifetime? 109 sec
A second is an arbitrary time unit, but one that is based on our experience. Our visual system is bombarded by snapshots at a rate of around 3 per second caused by rapid eye movements called saccades. Athletes often win or lose a race by a fraction of a second. If you earned a dollar for every second in your life you would be a billionaire. However, a second can feel like a minute in front of an audience and a quiet weekend can disappear in a flash. As a child, a summer seemed to last forever, but as an adult, summer is over almost before it begins. William James speculated that subjective time was measured in novel experiences, which become rarer as you get older. Perhaps life is lived on a logarithmic time scale, compressed toward the end.
What is the GDP of the world? $1014
A billion dollars was once worth a lot, but there is now a long list of multibillionaires. The US government recently stimulated the world economy by loaning several trillion dollars to banks. It is difficult to grasp how much a trillion dollars ($10 ) represents, but several clever videos on YouTube (key words: trillion dollars) illustrate this with physical comparisons (a giant pile of $100 bills) and what you can buy with it (10 years of US response to 9/11). When you start thinking about the world economy, the trillions of dollars add up. A trillion here, a trillion there, pretty soon your talking about real money. But so far there aren't any trillionaires.
How many synapses are there in the brain? 1015
Two neurons can communicate with each other at a synapse, which is the computational unit in the brain. The typical cortical synapse is less than a micron in diameter (10 meter), near the resolution limit of the light microscope. If the economy of the world is a stretch for us to contemplate, thinking about all the synapses in your head is mind boggling. If I had a dollar for every synapse in your brain I could support the current economy of the world for 10 years. Cortical neurons on average fire once a second, which implies a bandwidth of around 10 bits per second, greater than the total bandwidth of the internet backbone.
How many seconds will the sun shine? 1017 sec
Our sun has shined for billions of years and will continue to shine for billions more. The universe seems to be standing still during our lifetime, but on longer time scales the universe is filled with events of enormous violence. The spatial scales are also immense. Our space-time trajectory is a very tiny part of the universe, but we can at least attach powers of 10 to it and put it into perspective.
Managing Director of Excel Venture Management, authored As the Future Catches You and co-authored Homo Evolutis: A Tour of Our New Species.
Everyone is familiar with Digital Code, or the shorthand IT. Soon all may be discoursing about Life Code…
It took a while to learn how to read life code; Mendel's initial cookbook was largely ignored. Darwin knew but refused, for decades, to publish such controversial material. Even a term that now lies within every cheesy PR description of a firm, on jeans, and pop psych books…DNA… was largely ignored after its 1953 discovery. For close to a decade very few cited Watson and Crick. They were not even nominated, by anyone, for a Nobel till after 1960, despite the discovery of how life code is written.
First ignorance then controversy continued dogging life code as humanity moved from reading it to copying it. Tadpoles were cloned in 1952, but few focused until Dolly the sheep begat wonder, consternation, and fear. Much the same occurred with in vitro fertilization and Louise Brown, a breakthrough that got the Nobel in 2010, a mere 37 years after the first birth. Copying genes and dozens of species, leading to hundreds of thousands of almost identical animals is now commonplace. The latest controversy is no longer how do we deal with rare clones but should we eat them.
Much has occurred as we learned to read and copy life code, but there is still little understanding for what has occurred recently. But it is this third stage of life code, writing and re-writing, is by far the most important and profound change.
Few realize, so far, that life code is spreading across industries, economies, countries, and cultures. As we begin to rewrite existing life, strange things evolve. Bacteria can be programmed to solve Sudoku puzzles. Viruses begin to create electronic circuits. As we write life from scratch, Venter, Smith et al. partner with Exxon to try to change the world's energy markets. Designer genes introduced by retroviruses, organs built from scratch, the first synthetic cells further examples of massive change.
We see more and more products, derived from life code, changing fields as diverse as energy, textiles, chemicals, IT, vaccines, medicines, space exploration, agriculture, fashion, finance, and real estate. And gradually, "life code" a concept that only got 559 Goggle hits in 2000, and fewer than 50,000 in 2009, becomes a part of the everyday public discourse.
Many of the Fortune 500 within the next decade will be companies based on the understanding and application of life code, much as has occurred over the past decades with digital code leading to the likes of Digital, Lotus, HP, IBM, Microsoft, Amazon, Google, and Facebook.
But this is just the beginning. The real change will become apparent as we re-write life code to morph the human species. We are already transitioning from a humanoid that is shaped by and shapes its own environment into a Homo evolutis, a species that directly and deliberately designs and shapes its own evolution and that of other species…
Physicist, University of Aix-Marseille, France; Author, The First Scientist: Anaximander and the Nature of Science
The Uselessness of Certainty
There is a widely used notion that does plenty of damage: the notion of "scientifically proven". Nearly an oxymoron. The very foundation of science is to keep the door open to doubt. Precisely because we keep questioning everything, especially our own premises, we are always ready to improve our knowledge. Therefore a good scientist is never 'certain'. Lack of certainty is precisely what makes conclusions more reliable than the conclusions of those who are certain: because the good scientist will be ready to shift to a different point of view if better elements of evidence, or novel arguments emerge. Therefore certainty is not only something of no use, but is in fact damaging, if we value reliability.
Failure to appreciate the value of the lack of certainty is at the origin of much silliness in our society. Are we sure that the Earth is going to keep heating up, if we do not do anything? Are we sure of the details of the current theory of evolution? Are we sure that modern medicine is always a better strategy than traditional ones? No we are not, in none of these cases. But if from this lack of certainty we jump to the conviction that we better not care about global heating, that there is no evolution and the world was created six thousand years ago, or that traditional medicine must be more effective that the modern medicine, well, we are simply stupid. Still, many people do these silly inferences. Because the lack of certainty is perceived as a sign of weakness, instead of being what it is: the first source of our knowledge.
Every knowledge, even the most solid, carries a margin of uncertainty. (I am very sure about my own name ... but what if I just hit my head and got momentarily confused?) Knowledge itself is probabilistic in nature, a notion emphasized by some currents of philosophical pragmatism. Better understanding of the meaning of probability, and especially realizing that we never have, nor need, 'scientifically proven' facts, but only a sufficiently high degree of probability, in order to take decisions and act, would improve everybody' conceptual toolkit.