Why do we face people who are seemingly strange or different from us with caution? Why do we perceive strangers as threatening, even if there is no indication of danger? Even before a real encounter these kinds of situations enforce a certain behavioural pattern on the individual, one which makes us believe that the strangers are in fact a threat to us. The lecture deals with patterns of perception and regulatory schemes by which we divide our environment into certain antagonisms: us and others, the ‘good’ and the ‘bad’, the ‘civilised’ and the ‘savage’.