Aristotle was an ancient Greek philosopher and, together with Plato, is considered the "Father of Western Philosophy". He provided a complex synthesis of previous philosophers including Socrates and Plato, and Western philosophy and worldview inherited his fundamental intellectual lexicon, as well as methods of problem solving and research. The fact that Aristotle was Plato's disciple contributes to his early views on platonism, but later turned to the empiricism, believing that all concepts and knowledge are based on perception. Aristotle is credited with earliest research into formal logic, and his logic-based concept was the dominant form of Western logic until the 19th century. So, Aristotle built his ideas on logic.