Copycats and Contrarians has some chapters that will appeal to economists and experimental scientists, others that will appeal more to those interested in sociology, social psychology, and politics. The chapter on “Mavericks” stands out because mavericks have been neglected in the research literature; there has been much more analysis, at least in economic theory, of the copycats than the contrarians in our world.For original scientific research, the chapter “Herding on the Brain” is the most interesting. Here I present some of my seminal research with Cambridge neuroscientists, including Professor Wolfram Schultz and his group, that explored some of the neural correlates of herding behavior. Wolfram Schultz is one of the pioneers in neuroeconomics – a relatively new subfield of economics which brings together economic insights with neuroscientific analysis. We used brain imaging techniques – specifically functional magnetic resonance imaging – to monitor our experimental participants’ neural responses while engaged in a stock-picking task.For this experiment, our participants were given two pieces of information. First, some non-social information about a financial stock was presented in the form of a stock performance chart. Second, some social information about what other people had decided to do was also given to participants. Essentially, our participants were being asked either to stick with their own judgements based on the financial information that we’d given them, or, alternatively, to copy others’ decisions.We found that most people, around 70%, copied others; this result is consistent with other experimental studies. The brain scans were more surprising; they showed some complex interplays of neural response. Copying others was associated with activations in areas of the brain usually associated with emotional processing. Copying others was also associated with activations in areas of the brain usually associated with higher level analytical reasoning.From these experiments, it seems that herding reflects a complex interplay of reason and emotion. These findings connect with new insights into dual systems thinking, i.e. System 1 (emotional, automatic) versus System 2 (cognitive, deliberative), popularised by Nobel Prize-winning economic psychologist Daniel Kahneman in his 2011 book Thinking, Fast and Slow.To capture the overall point of the book, the final chapter argues that social media and online social networks have perverted our instincts to follow others. Social information and social feedback travel rapidly and in large volumes via our online social networks. Added to this, the anonymity of online interactions means that people do not have to take the same responsibility that they have to take when interacting in more traditional contexts.The pre-online equivalents of Twitter trolls and cyber-bullies, for example, may have had the inclination to persecute others but the channels for their anti-social behaviors were limited, and the chances of being detected and suffering social sanctions were larger. More benignly, memes can circulate and multiply online in ways that would have been unimaginable even 20 years ago.Online, we tend to gather in echo chambers; most of us are selective about who we follow online and we tend to follow those who share our opinions. In these echo chambers, herds of voters quickly reinforce each other’s social opinions and partisan political positions. So herds’ opinions are magnified much more quickly than in the past, tipping over into impactful, real-world choices– for example, voting patterns. We may dismiss online opinion as ephemeral and diffuse but when it generates herds of people reinforcing specific political and social positions, and if these online herd opinions change people’s behavior, there will be wide-reaching consequences.One solution would be to institutionalise mechanisms to preserve contrarian opinion - for example by protecting mavericks and contrarians, including whistle-blowers, from vilification and ostracism. Given that humans are inclined to be copycats most of the time, our world urgently needs more contrarians to ensure that wrong-headed conventional wisdoms cannot persist for too long.