Chapter 5 on consciousness explains the many boundaries of psychological analysis. In the section on stimulants, I found the information on cocaine to be the most interesting. Cocaine is the most powerful natural stimulant. Users commonly experience euphoria, enhanced mental and physical capacity, a decrease in hunger, indifference to pain, and a sense of well-being.
One part in the book took me by surprise as I read that the soft drink Coca-Cola used to contain small amounts of cocaine, and was advertised to "cure your headache and relieve fatigue for only 5 cents," (pg. 192). I had heard rumors of cocaine being in my favorite pop, but never really believed it until now. It was easy to see why cocaine was used in common products like soft drinks, because back then when cocaine was a new drug in the market in the late 1800s, doctors hailed cocaine as a cure-all and prescribed it for a wide range of illnesses. I'm sure when a medical doctor says a new drug is "all-curing" it's hard not to believe so.
Even the great Sigmund Freud supported the use of cocaine to treat morphine addiction and he used cocaine to improve his mood. However, he changed his ideas and disapproved of its use when he had dependence problems. Cocaine came under strict government control in the United States in 1906.