Social Learning Strategies

We decide what to believe by deciding who to believe

Social learners can acquire more adaptive knowledge at a lower cost, and without having to generate the information, do so with a smaller brain. Larger groups of social learners with more adaptive knowledge create a selection pressure for an extended juvenile period to acquire this knowledge. Under some circumstances, this can lead to oblique learning and selective biases to distinguish who to learn from—the human pathway to truly cultural brains.

—Michael Muthukrishna and Joseph Henrich, Innovation in the collective brain, March 2016 (henceforth MH)

Henrich points out that what he calls The Secret of our Success as humans is the way that we share and expand knowledge. This is a social process.

In 1957, Bert Weedon, a British musician, published Play in a Day, a book of guitar lessons. Many British teenagers were inspired and guided by Weedon. A tiny subculture of these teenagers became entranced by the sound of blues that originated in the American South (many of the musicians themselves migrated to Chicago). They sought out vinyl recordings made by American blues musicians, most of whom were black and little known in the United States. As they played these records over and over, learning to copy the the chord progressions and string-bending techniques, the few dozen blues-obsessed teenage British guitarists eventually became aware of one another. They became mentors to one another, sharing playing skills and equipment designs. By 1969, this small subculture had formed the Beatles, the Rolling Stones, Cream, The Who, Led Zeppelin—bands that dominated the hard rock genre at the time.

As MH point out, humans have large brains, and we have been able to adapt to every environment on earth. But as individuals we are helpless without the knowledge obtained from others. Instead,

Our societies and social networks act as collective brains. Individuals connected in collective brains, selectively transmitting and learning information, often well outside their conscious awareness, can produce complex designs without the need for a designer—just as natural selection does in genetic evolution. The processes of cumulative cultural evolution result in technologies and techniques that no single individual could recreate in their lifetime, and do not require its beneficiaries to understand how and why they work

MH suggest that because we are social learners, larger groups are more adaptive. Because we share what we learn, as more experiments are tried, we can discover new techniques that work.

MH also point out that we require a long juvenile period so that cultural knowledge can be transmitted. Species that instead rely mostly on instinct are able to act as adults much sooner, because they require less instruction.

As individuals, we have an instinct to learn from people who seem like us and from people who have prestige within our circle. But culturally we have evolved also to learn from people who are different from us and people who are distant from us, as the American blues musicians were distant from British teenagers.

MH argue that innovation usually involves the interaction of many brains.

There are many examples where ‘new’ inventions are more clearly the product of incremental improvements, recombinations of existing elements and selection; the ‘inventor’ is really just the popularizer

Luke Rendell, Kevin Laland, and co-authors used computer simulation to conduct a tournament that demonstrated the benefits of using others’ knowledge. In Why Copy Others? Insights from the Social Learning Strategies Tournament, they gave participants in the tournament the choice of three moves. One move, that they called Innovate, was to engage in asocial learning, meaning trying something new on your own and seeing whether it worked. Another strategy, Observe, meant simply watching others to try and learns what works and what does not. A final strategy, Exploit, meant using whatever knowledge had been obtained by Innovating or Observing.

The authors found in their tournament simulation that learning by Observing was more efficient that learning by Innovating. That is, social learning dominated asocial learning. This was true unless the simulation was tuned to have such a highly variable environment that the value of social learning decays too quickly to be useful. The authors explain,

social learning proved advantageous because other agents were rational in demonstrating the behavior in their repertoire with the highest payoff, thereby making adaptive information available for others to copy.

Laland, in his book Darwin’s Unfinished Symphony, argues that humans evolved language in order to improve teaching. Our theory of mind also was developed to improve teaching. He argues that fidelity of copying is very important for learning. This would imply that developments like writing, the printing press, computers, and the Internet all would dramatically enhance social learning.

Once we accept the social learning hypothesis, this raises some difficult questions.

To what extent are our desires copied from other people, and what are the consequences of this? Rene Girard is known for arguing that this accentuates competitiveness—if we all want the same thing, then we will compete for it.

What does it mean to think for yourself? I do not conduct experiments in physics and chemistry. Instead, I trust the teachers and books that explain those subjects. I argue that we decide what to believe by deciding who to believe.

How can we determine the best people to believe? What criteria should we use? We might use credentials (“Jack is a licensed physician”), but that heuristic does not always work. I favor people who “show their work,” meaning that they can explain their thought process. Also people who show an ability to weigh different points of view, as indicated by the “fantasy intellectual teams” criteria of being able to play Devil’s Advocate, to think in terms of bets, to mention caveats, to engage in civil debate, to explain what would make them change their minds, to evaluate research, and to steel-man the views of those who disagree.

This essay is part of a series on human interdependence.