Philosophical pluralism's core belief consists of the notion that humans do not simply discover and copy, through the use of reason, a unified reality that exists independently of them. Rather, our view of reality, or that which we take as truth, is always influenced by our cultural and historical context. Truth, accordingly, can never be absolute, static, strictly objective, and monolithic. On the contrary, it always contains elements of subjectivity and change, more of relativism than absolutism. In short, truth, and even reality itself, consist of the many rather than the one.
Absolutism, on the other hand, holds that the human mind acts ideally as a passive mirror that faithfully reflects an independently existing, unified reality without distortion. Universal agreement about the nature of that reality is therefore possible. This notion was most famously articulated by the ancient Greek philosopher Plato (c. 428–348 or 347 B.C.E.). In his allegory of the cave, Plato regarded the knowledge of ordinary people to be distorted by the conventions of culture and the flux of change typical of the empirical world of passing phenomena. Plato's philosopher, on the other hand, abandoned the cave of culture and walked outside into the light. There he apprehended the eternal, the unchanging, the very essence of all being—the pure Idea. Thus Plato's philosopher rose above myth, deception, and error, above the darkness of the empirical world typical of the cave of ordinary life. He transcended all limitations to achieve objective, transparent, and timeless truth through the exercise of unconditioned reason. With his mind thus unfettered, the philosopher should also assume the political authority of king in the ideal republic because he alone could rule on the basis of truth and reason. Plato thereby introduced the undemocratic view that only those with privileged consciousness should rule.