Plato is probably the most important philosopher to have ever lived, in part, because he is the first systematic philosopher. Yes, there were other philosophers before Plato, and yes, there are some more influential philosophers after Plato. But Alfred North Whitehead’s statement that “the safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato,” reflects the importance of Plato for establishing the systematic foundation for the Western philosophical discipline and project.
Greek philosophy can roughly be broken up into three eras: (1) the Pre-Socratic, (2) Sophist, and (3) Classical eras. When most people think of philosophy, and Greek philosophy in particular, they think of the classical era which begins with Socrates as accounted for in Plato’s Dialogues. The Pre-Socratic era was lively but singularly focused on metaphysics (first principles of existence). Thales was the father of the Ionian school, and Thales asserted that all reality was made of water. Now what Thales meant by that was that all reality could be reduced to a single source (metaphysical monism) and that this source, “hydor,” was constantly in flux and ever changing – this was his way of accounting for why all things in appearance seem to constantly change and are never the same. The Ionian school, which included his disciples and interlocutors Anaximander and Anaximenes, debated among themselves over what that single source was. Eventually they were challenged by the metaphysical pluralists, led by Anaxagoras, Empedocles, and the Pluralist School which asserted that reality was composed of more than one source (pluralism meaning more than one).
Eventually the Pre-Socratic era came to an end at the end of the sixth century with the rise of the sophists and nihilists. The Greek sophists and nihilists are featured prominently in Plato’s Dialogues, and always serve as the foils and interlocutors to Socrates. The Sophist era marks the turn away from metaphysics and the concentration of ethics and political philosophy. Now, the sophists and nihilists are sometimes conflated together – we must first explain these movements since Plato spends much time dealing with them and his philosophy can only be properly understood with the sophists and nihilists in the background.
Pre-Socratic metaphysics was the attempt to understand the nature of reality and existence. While the Ionians and their challengers never established a systemized epistemology (theory of knowledge), epistemology must be contingently relevant to any philosophy that asserts that there is truth and we can come to know it. The failure of the Ionians and Pluralists to establish such an epistemology led to the sophists turning away from metaphysics and concentrating in ethics. The sophists claimed that while there was truth, we could never know truth. So we shouldn’t bother with trying to know that which we can never come to know. Instead, the only thing we could know was the social constructions of human political society and that the study of political ethics is what we should concern ourselves with. On the whole the sophists advanced a form of ethical egoism in their ethics. Ethical egoism is the view that self-interest and self-advancement is the only proper form of ethics. The nihilists, while not necessarily disagreeing about ethical egoism, took the more radical view that there was no truth whatsoever, and everything was simply what humans made of their life and time on earth.
Now the sophists share a similarity with contemporary postmodernism in many ways, but what separates the Greek sophists from contemporary postmodernism is that the sophists didn’t actually see ethical egoism, self-advancement, and “justice as being whatever is in the interest of the strong” as bad things. After all, the sophists were teachers to the young Athenian nobles who would one day come to positions of power. The sophists were basically teaching them how to “game the system” to use modern parlance. The sophist era is dominated by the rejection of metaphysics and the concentration with self-advancing ethics.
This is the backdrop to the emergence of Plato. Plato, admittedly, thought that the sophist tradition was horrible and chaotic. Plato sought to assert the opposite in challenging the sophists: there was truth (by the admission of at least the sophists) and we could come to know truth. This would also mean that self-interest and self-advancement ethics (ethical egoism) was also wrong. Plato establishes the beginning of foundationalist philosophy – the belief that there are universal foundations for knowledge and human action. Truth, by definition, needs to be universal and foundational otherwise it is not actually truth. Plato, then, is the individual who establishes the systematic epistemology that the Ionians and Pluralists were lacking.
Plato’s most famous allegory, the Allegory of the Cave, reflects his epistemological foundationalism. The Allegory of the Cave embodies Plato’s epistemology and thoughts concerning the sophists. The Cave represents the world of socially constructed opinion that is passed off as knowledge and wisdom. It is a cold, dark, and ultimately unhospitable place for people actually interested in knowledge and wisdom. The world outside of the Cave, filled with the pleasantries and warmth of the Sun, represent the world of the Forms (Plato’s own philosophy). The philosopher is the person who is interested in wisdom and truth, which means that person is interested in coming to know the Forms. In the Allegory, the person leaving the Cave is the philosopher – but as Plato recounts, his first encounter with the light of the sun is so shocking that it causes him to return back to the world of conventional opinion (the Cave). However, his curious appetite has been whetted so he goes out in search for the light again and eventually makes his way out of the Cave. This represents the coming to understanding, or the coming to know knowledge – the Forms. But Plato warns that the philosopher who returns to the Cave to “enlighten” the sophists and their ilk will be killed by Cave and the leaders of the Cave.
The manner by which someone can come to know The Forms is twofold. But first, we must understand that Plato maintains that humans have innate ideas (that is to say, we have natural inclinations to ideas and concepts, e.g. one may not know the form of beauty but one knows beauty when they come across it in the real world). In other words there is no Tabula Rasa or Blank Slate as Locke and the empiricists had it. Therefore, the innate ideas (or innate desire) that humans have is the natural spark of curiosity that leads humans to pursue wisdom. Aristotle built upon this Platonic idea in Metaphysics when he asserted that “all men by nature desire to know.” So first is reason alone seeking to understand the innate ideas that stimulate it. This is Plato’s rationalist epistemology – the primacy of reason over experience or sensation. According to Plato a person can know the Forms by pure rational introspection. (This is later challenged by Aristotle not as a rejection of the importance of rationality to epistemology but a warning as to why reason and experience is a superior manner to attain knowledge than reason alone.) The second manner to understand the Forms is what is most commonly presented throughout the Dialogues: the Socratic Dialectic. The Socratic Dialectic is system of questioning and introspection among two or more parties on a given topic, and through this questioning, introspection, and dialogue that follows, we are engaged in a rationally thinking process by which we can come to a conclusion that hopefully reached the nature of the Forms.
To return to the first manner by which we come to know knowledge. Plato’s innate ideas of the Forms mean that all humans already have some knowledge of the Forms. These innate ideas which reflect the Forms serve as a blueprint, or guideline, for our lives and actions. For instance, it doesn’t take a philosopher to know beauty when walking in a beautiful field and coming across a field of flowers. Any person, unless deliberately suppressing their innate ideas, can look upon the flowers and know that they are beautiful. That person may not truly know the Form of Beauty, but that person’s innate inclination of beauty kicks in and reflects the innate idea that all have, or will be the spark that leads the person into the philosophical life. The Forms, as Plato recounts, are like “sweet nectar” that enticingly draws and allures people to its sweetness. The coming to know the Forms is humanity’s telos (or end), because Plato asserts that knowledge begets happiness. True happiness is only possible through true knowledge.
Plato also believes that the world is orderly and rational, thus human reason is an ordering force the guides our innate ideas back to the source (the Forms). The sophists and nihilists represent chaos and disorder precisely because they deny the Forms (the nihilists) or they deny that reason can order our innate ideas (or desires) to come to know knowledge (the sophists). The result of this outlook is an “everyman for himself” mentality and lifestyle that breeds confusion and chaos (which is the world of the Cave). Plato, however, ends by believing that few people will become philosophers and must will remain suppressing their innate ideas and prefer to live in the false glory of the Cave. The Cave accepts idiocy as knowledge and threatens those with true knowledge with violence and potential death. The end result of Plato’s outlook is that the philosopher detaches himself from Cave society in his pursuit of happiness, which is the pursuit of knowledge – the satisfying of the innate ideas or desires which humans have. In a way, Greek Stoicism and Cynicism reflected a certain Platonic quality and character to it – this view was later challenged by Aristotle and the Roman Stoics who agreed, in principle, with Plato that there was truth and we could know it, but that this didn’t require, or entail, separation from society.
Nevertheless, Plato is instrumental in establishing foundationalist epistemology: there is truth and we can come to know truth (he locates this truth in the realm of the Forms, which is the eternal, transcendent, forms of beauty, justice, goodness, etc. which are universal and valid at all times). This does not mean that we do know truth or people claiming to know truth are speaking truthfully however (there are plenty of ignorant people out there). Thus, foundationalism demands some form of skepticism. Skepticism is not nihilism. But Plato’s skepticism is not the skepticism of the sophists who assert we can never really know knowledge. Plato is just warning us to be weary of those preaching knowledge (and this becomes a running theme that gets picked up by people like Aristotle, Augustine, and well into the 19th century with the likes of someone like Joseph de Maistre). This is why Socrates always questions his dialogue partners. Though we are skeptical of those claiming knowledge, the impetus for this is that we, ourselves, begin introspecting and journey to the Forms for ourselves.
The manner by which we come to know truth is through pure reason, which demands the cultivation of the human mind to understand the a priori, or the innate ideas that are already within us. This is called “classical rationalism” in epistemology, and differs radically from the blank slate “reason” epistemology of modern philosophy. This needs to be remembered when the scions and Hobbes, Locke, Spinoza, and Kant use the term “reason” in contradistinction to the scions of Plato: the Platonists and neo-Platonists, who also use the term reason as instrumental for coming to know truth. The former assert reason is what socially constructs and brings understanding to what we observe (empiricism), the latter assert that reason is what satisfies our innate ideas and desires (rationalism).