The Nicomachean Ethics is Aristotle's best-known work on ethics, the science of the good for human life, which is the goal or end at which all our actions aim. Based on lectures Aristotle gave in Athens in the fourth century BCE, Nicomachean Ethics has profoundly influenced the whole course of subsequent philosophical endeavour. It consists of ten books or scrolls, understood to be based on notes from his lectures at the Lyceum and It offers seminal, practically oriented discussions of many central ethical issues, including the role of luck in human well-being, moral education, responsibility, courage, justice, moral weakness, friendship and pleasure, with an emphasis on the exercise of virtue as the key to human happiness.