Plato is generally considered the greatest figure in the history of human philosophy. His approach to philosophy and his use of terminology have echoed through Western philosophy for thousands of years. Today, his exact positions are rarely held, and many (if not most) of his arguments have been modified or altered in the thousands of years since his death. However, it would not be an exaggeration to say that Plato’s influence can be seen in the style—if not the content—of virtually all metaphysical discourse that has ensued.
Plato put forward a version of the cosmological argument, which is used to defend the idea of a single, all-powerful God. His views on truth and absolute morals are extremely similar to those of Judeo-Christianity. He also believed that there was an immortal component to all human beings; however, in Plato’s case, this involved a version of reincarnation. Plato’s concept of God was of one who continually formed out of chaos, rather than out of nothing. He also held that the body and soul were completely separate, such that the body was inherently inferior to the soul. And his stance on morals held that moral behavior was always a matter of education.
Living around the turn of the fourth century BC, Plato was not the first philosopher to take a rational, organized approach to thinking. In that regard, Plato was not a groundbreaking theorist. What truly sets Plato’s work apart is the combination of broad scope and useful terminology. By writing about an incredibly diverse number of topics and doing so using specific, consistent, well-identified terms, Plato made his work indispensable for millennia to come. While it is true that Plato influenced many writings, it is important to note this influence is primarily methodological, not necessarily spiritual or religious.
Those who came after Plato, adapting his approach, are sometimes labeled Platonists or adherents to Platonism. Both of these terms are wide-ranging. However, they share a common belief in the cornerstone of Plato’s metaphysics: a belief in “forms.” These forms, according to Platonic thinking, are universal, objective truths. These ideas themselves are not, according to Platonism, beings or persons.
As a technical term, rather than as a school of philosophy, Platonism is a reference to a belief in abstract objects. In brief, this means accepting the existence of some things that do not exist either in the material world or in the mind, but in some “other” aspect of reality. This, in and of itself, has only a tenuous connection to Plato’s own philosophy or the various schools of Platonism.
Concerning Judeo-Christianity, Plato’s influence is considerable, though indirect. Judaism developed its central beliefs and was given the Scriptures centuries prior to Plato’s birth. While there are some parallels between Hebrew metaphysics and Plato’s, history would imply that interactions with Platonism, if any, would have been influences from Judaism, not on it.
On the other hand, the New Testament was written in an era steeped in Greek philosophy, especially Platonism and related schools. Christians were frequently called on to oppose worldviews grounded in these schools of thought. And the dominant forms of writing used at that time were almost entirely drawn from the work of men like Plato. For that reason, it would be completely correct to say that Christianity relies heavily on Plato when using philosophical terms. Yet this no more means that Plato formed Christian thinking than widespread use of Carl Linnaeus’ taxonomic system proves that Linnaeus formed animals.
In other words, the modern Christian world owes Plato much, since Plato provided words and topics with which we can meaningfully discuss Judeo-Christian ideas in the Western world. His methodology is, in fact, something virtually all Western philosophy has been affected by, in that same sense. But the factual, religious, and moral ideas of the Christian faith long predate Plato, show no evidence of being influenced by Plato, and are not dependent on him or his writings.
In short, Platonism indirectly affected Christianity by providing two things: a common style of logical discourse and an opposing worldview to which Christianity could be presented as an alternative. Writings of the early church fathers, particularly after the second century, show a heavier reliance on Platonic terminology and arguments than do the writings of the New Testament era.