simple answers...

"The unacknowledged assumptions of the scientist will often limit and define what will be discovered. Settling for the view that illnesses, mental or physical, are primarily genetic allows us to avoid disturbing questions about the nature of the society in which we live. If 'science' enables us to ignore poverty or man made toxins or a frenetic and stressful social culture as contributors to disease, we can look only to simple answers: pharmacological and biological. Such an approach helps to justify and preserve prevailing social values and structures. It may also be profitable."

(Gabor Mate MD)