The Ancient era starts with the [[Presocratic Philosophy|Presocratic]] philosophers and goes until the fall of the Roman empire; The Medieval goes until the end of the [[Middle Ages]]; The Modern up to the 20th century, and The Contemporary up to present. | The Ancient era starts with the [[Presocratic Philosophy|Presocratic]] philosophers and goes until the fall of the Roman empire; The Medieval goes until the end of the [[Middle Ages]]; The Modern up to the 20th century, and The Contemporary up to present. |