Philosophy is sometimes dealt with "big questions"; What makes things correct or morally wrong? How can you know that the world around you is real and that it is not a hypothetical fact created by the computer? Does what our eyes see is the real world, or just imaginations? Do we have souls? This book is written by five professors specializing in philosophy, in universities from different countries to discuss the most prominent philosophical ideas throughout history, in the simplest and enjoyable ways, so let us.