Psychologists suggest that to cure cruelty

3. The author of the passage illustrates that the mathematician

1. 
   died in the fire which the story refers to
   
2. 
   was contented just to know that the fire could be extinguished
   
3. 
   was much cleverer than the engineer or the physicist
   
4. 
   wasn't woken up by the fire in the hotel he was staying in
   

If people are satisfied where they are, they will not migrate. Throughout history, people have left their native lands for a variety of reasons: religious or racial persecution, lack of political freedom, economic deprivation. The forces that attracted them to new homelands were the opposites of these: religious and political freedom, ethnic tolerance, economic opportunity. The leading motive behind migration has always been economic. Overpopulation creates shortages of jobs and food. The natural resources of a region can become exhausted, impelling a whole group of people to migrate. People who are oppressed for any reason will in all likelihood be economically deprived as well. The movement from farm to city is a prime example of migration for economic reasons. During the Industrial Revolution of the 18th and 19th centuries, millions of people left poverty-stricken rural areas for the cities. Even the low-paying, seven-day-a-week jobs in early factories were better than the endless toil and misery of trying to earn a living on the farm. This search for jobs in urban areas has continued to be a leading cause of migration up to the present.

1.