From The Long Now Foundation (<a href="https://www.flickr.com/gp/jurvetson/61eG76">Panel on Possible Minds</a>):

“Consider the so-called ‘filter bubble’ of social media. The reinforcement learning algorithm is trying to maximize click throughs. From the view of the human, the purpose of the machine is to maximize clickthroughs.  But from the view of the machine, it is changing the state of the world to maximize clicks.  It is changing you to make you more predictable.  A raving fascist or communist is more predictable and will lap up raving content. The machines can change our mind about our objective function so we are easier to satisfy. Advertisers have done this for decades.” [I argued with him about this feedback loop, and Yann Le Cun says this changed at Facebook a while ago]