Book Excerpts: From Chocolate To Morphine (co-authored by Andrew Weil)

The approval of some drugs for some purposes usually goes hand in hand with the disapproval of other drugs for other purposes.  For example, some early Muslim sects encouraged the use of coffee in religious rites, but had strict prohibitions against alcohol.  On the other hand, when coffee came to Europe in the seventeenth century, the Roman Catholic Church opposed it as an evil drug but continued to regard wine as a traditional sacrament.

Everybody is willing to call certain drugs bad, but there is little agreement from one culture to the next as to which these are.

p. 11 (What is a Drug?)

Students of behavior tell us that dividing the world into good and evil is a fundamental human need.  The existence of evil provokes fear and demands explanation.  Why is there sickness?  Why is there death?  Why do crops fail?  Why is there war?  And, most important, how should we act to contain evil and avoid disaster?  One attempt at a solution is to attibute evil to external things, and then prohibit, avoid, or try to destroy them.  This is how taboos arise.
p. 12