To some extent man has been able to free himself from these difficulties.  Thousands of years ago he learned to increase his food supply and, more recently, he has learned to control his reproduction.  Yet while man enjoys certain advantages when compare with other living things, he also suffers from certain disadvantages.  Unlike the various plants and animals, man has an insatiable appetite for goods and services.  No matter how much he produces and consumes, he always desires more.  This is true chiefly because the goods and services he consumes have a status value as well as a utilitarian value (1966, p.31).