This lecture addresses several important questions on the interface between technology and society:

• Why our world becomes ever more complex?
• Can we cope with world complexity?
• What is the relation between freedom of speech and information filtering?
• What is the psychological background of on-line cults and conspiracy theories?
• Why negative views propagate faster?
• What is the relation of irrationalism, and anti-elitism, to social media disinformation?
• How can we valorize our private data?