Charles Mackay on the three causes of discontent of mankind

Three causes especially have excited the discontent of mankind; and, by impelling us to seek remedies for the irremediable, have bewildered us in a maze of madness and error. These are death, toil, and the ignorance of the future.

~ Charles Mackay, Extraordinary Popular Delusions and the Madness of Crowds, "Understanding the Forces Behind Group Mentality, Thoughts and Actions,” p. 104