It may be said that every individual man and all men in common aim at a certain end which determines what they choose and what they avoid. This end, to sum it up briefly, is happiness and its constituents. Let us, then, by way of illustration only, ascertain what is in general the nature of happiness, and what are the elements of its constituent parts. For all advice to do things or not to do them is concerned with happiness and with the things that make for or against it; whatever creates or increases happiness or some part of happiness, we ought to do; whatever destroys or hampers happiness, or gives rise to its opposite, we ought not to do.
Aristotle was an ancient Greek philosopher, student of Plato and teacher of Alexander the Great, a naturalist, creator of reason and the most important of dialects of antiquity. Born in Stagira, his father Nicomachus was the physician of King of Macedonia Amyntas III, grandfather of Alexander the Great. His parents died when he was young and had to come into the custody of a family friend who lived in Atarneas opposite of Lesbos. This man brought Aristotle up as his own son and sent him to Athens at the age of 17 years, to become a student of Plato where he stayed or 20 years (367-347).
After the death of Plato and as Spefsipous took over the management of the Academy, Aristotle went along with Xenokratis, also philosopher and student of Plato, and settled in Assos, a city in Asia Minor, opposite Lesbos. In Assos, Aristotle taught for three years and managed to influence the tyrant Hermias so that he ruled much fairer.
In 345 BC he settled in Mytilene, where he lived and taught until 342 BC In the meantime he had married the niece and adopted daughter of Hermias, Pythia, with whom he had a daughter. After the death of his first wife Aristotle had a relationship, later in Athens, with the Stageiritissa Erpyllida , with whom he had a son, Nicomachus .
In 342 BC Philip invited him to Macedonia for the education of his son Alexander, who was then only 13 years old. He began teaching the young heir by using the Homeric epics and imparting him the Panhellenic spirit.
He stayed at the Macedonian court for six years and then he went to Athens (335 BC) and founded his own philosophical school, the Lyceum. With money provided unsparingly from Alexander, Aristotle built magnificent houses and galleries, the organization of the faculty was modeled on the Platonic Academy. Aristotle gathered maps and instruments for teaching the natural courses and the school soon became famous center for scientific research . There was a large library and so well organized, that later served as a model for the establishment of libraries of Alexandria and Pergamum. In thirteen years Aristotle created the main bulk of his work, which causes great admiration; he wrote 400 books of which 47 survived .
In 323 BC with the news of the death of Alexander the followers of antimakedonian party thought they were going to avenge the Macedonians in the face of Aristotle. He was accused of impiety, so Aristotle fled to Chalcis to avoid the trial, along with his second wife and his two kids. He died the same year in Halkida from stomach problems, in sadness and melancholy .