Have you ever found yourself alone with your thoughts? Have you ever been asked if the glass is half full or half empty? Do you wonder what true happiness is or how to attain it? Or maybe nothing really matters if everything is just an illusion or a dream? These ideas are some of the central questions of philosophical enquiry that have engaged and exasperated some of the greatest minds throughout human history, provoking argument and debate in an attempt to broaden the horizons of human thought. Author Alain Stephen seeks to explore some of these key questions by tracing their origins in the writings of prominent thinkers through the ages, from the colonnades of ancient Greece to the intellectual salons of 20th-century France, and show how these ideas and concepts have developed over time.