Social media is based on continuous positive feedback from other users on user messages. The operators of these platforms have an obvious interest in ensuring that users spend as much time as possible on their platforms, and to do this they have a wealth of data about what content is likely to be attractive to users. This leads to an increasingly strong conviction of the user's own truth in a community of positive feedback, even if that truth is based on completely nonsensical or deliberately manipulative facts. There have certainly been adherents to the flat-earth theory, anti-vaccinationism, the chemtrail theory - that the contrails on aeroplanes are evidence that aeroplanes are spraying poison at us - or even the illuminati conspiracy that runs the world. But these delusions are much less dangerous when dispersed, with a lone proponent, than when the believers in the counterfactuals are constantly reinforcing their delusions in a virtual network. Fake news, which is cheap to produce, professional in its ability to capture users' attention, and therefore spreads at lightning speed on social platforms, has become more visible and more influential than ever before. Platform-based media have a major role to play in this, even if it is not Facebook, YouTube or Twitter that have obviously caused the underlying, serious social problems.

In processing information, we try to achieve the greatest possible benefit with the least possible effort, and the benefit is ultimately the satisfaction of the information we obtain, the sense of being at home in the world. We are more likely to take in information, and more effectively, if it provides us with a simple, accessible explanation of the world and helps us to place ourselves in different communities.

Among cognitive weaknesses, the most dangerous is underestimating our own limitations, overestimating our abilities. The so-called third-person effect leads us all to make sure that the news we read is reliable and infallible, that our decisions, unlike those of others, are always based on real facts, and that we, unlike others, are protected against cognitive biases. Only others can be fooled, not us. We believe we understand context better than anyone else, we are more resistant to manipulation, we are better able to distinguish the untrue from the true. Moreover, we always see ourselves vindicated in hindsight. Whenever we say "I knew it all along", we are always hiding behind so-called hindsight reasoning.

Of course, we can only work from the information we have, so we magnify the phenomena we know about, while ignoring explanations that would require additional effort on our part to understand (availability heuristics). In essence, the defining feature of all religions is that they substitute mystical elements for ignorance, for a limited ability to understand events.

Our weaknesses also include confirmation bias, i.e. the involuntary selection of information that reinforces our worldview and fits the pattern of how we think about reality. This is why we prefer to read news sites that tell us what we already think about the world, and why Facebook increasingly shows posts by people we know and react to more often. Confirmation bias locks us into an information bubble, an information comfort zone, even when we encounter information and opinions that otherwise contradict our own. The more we move in a medium that reinforces our own position with constant positive feedback - likes - the more we reject contradictory information. Such information can make us disinterested or angry, but if the bubble is strong enough, it certainly won't make us reconsider our own position. Instead of dialogue and debate, the information bubble allows at most angry exchanges.

So the first step in defending ourselves against fake news is to accept that we can be fooled.

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