Hutton lived during a time often called the Age of Reason, which began in the late 1600's and lasted through the 1700's. During this period, scientists emphasized the importance of using careful observation and experimentation to discover the laws by which nature operates. This emphasis led to the development of the modern scientific method. Edinburgh during this time became known as the Athens of the North, and the city had no equal as a center of scholarship and intellectual activity. In addition to Sir James Hall, Hutton's close friends in Edinburgh included Joseph Black, the chemist who first identified carbon dioxide; Adam Smith, the economist who first stated the principles of capitalism; James Watt, the inventor famous for his improved steam engine; and Robert Adam, an architect and furniture designer known for his elegant neoclassical designs.