Basic economics

"Why are homeless people sleeping on the sidewalks of New York in the winter, when the abandoned apartment buildings in the city have four times as many dwelling units as there are homeless people in the city? Why are people hungry in Moscow when there are vast amounts of some of the richest farmland on the continent of Europe within easy driving distance? Why did unemployment reach 25 percent and American corporations as a whole operate in the red for two years in a row during the Great Depression of the 1930s?". "All these very different - but equally puzzling and needless - tragedies grew…