Like humans that are unique among all living things, philosophy has an extraordinary nature compared with other disciplines of knowledge. Philosophy is an ancient discipline of knowledge. It originated in China approximately 1000 BC and in the West approximately 700 BC. It is truly time-honored and long-standing. Surprisingly, however, such an established discipline finds it difficult to categorize itself properly and to agree on its research questions. The historical development of philosophy has led to constant debates on what kind of discipline it is and what its research subjects should be. To date, no agreement has been reached. Differences abound among philosophers, schools, eras and nations. Philosophers are concerned with their own domains and questions, which are seldom the same. For every new era when a new philosophy emerges, the same old question will be asked, namely, “What is philosophy?” The answers start from that era. Philosophy is commonly seen to start and restart always from scratches but then stand still without making any progress over the three thousand years of development. This is inconceivable in other theoretical disciplines.