Roman philosophy after the Greeks and prior to the Christians was dominated by four schools of thought: the Stoics, the Skeptics, the Epicureans, and certain metaphysical Mystics. The Stoics got their name from the fact that they used to walk around philosophizing on the porch of the marketplace in Athens. The Greek word for porch is “Stoa”. These thinkers, led by one Zeno (334-262 BCE) were best characterized by their belief in the absolute rationality of the way of the universe.
The Stoics were rationalistic materialists, believing that reality is essentially physical and that its ways can only be understood by way of rational principles. At the same time, however, they also thought that the only way for humans to be happy as well as good is to follow a totally rational way of life. Emotions must never be allowed to cloud one’s reasoning.
Surprisingly, the Stoics also believed that the universe is Divine, making them “pantheists”. One problem with which they had to deal was the co-ordination of their belief in the divinity of the universe and the human capacity for freewill. If the Universe is divine and rational, it would seem that there would be no need for or possibility of human choice. Everything should simply follow the Divine will.
Nonetheless, humans are very often faced with choices between the right or good and what is wrong or evil. This logical difficulty dogged Stoic thinkers throughout their period of dominance. Aside from Zeno the most prominent Stoics were Epictetus and the Emperor Marcus Aurelius. It has remained a puzzle just how an Emperor can believe that the course of the world is fully determined and still make responsible decisions about issues daily facing the Empire.
Pretty much the polar opposite of the Stoics were the Epicureans. Following the teachings of Epicurus. These thinkers sought to follow the values of a life of pleasure. It is from them that we, erroneously, get the term ‘epicurean’ for someone who knows and enjoys fine foods and wines. The followers of Epicurus sought happiness, not crass pleasure, and argued that this is the natural and rational way of life. They sought peace of mind and a balance of the emotions so as never to be off-balance emotionally. They lived in a secluded Garden where they could practice self-control and the pleasures of the mind. They differed markedly from the “hedonists” who sought pleasure for its own sake.
The Skeptic school of Roman thought claimed that it is not possible to know the truth about what is real, good, etc. and thus one should avoid committing oneself to any one school of thought or any ultimate conclusions. The Skeptics taught that the only truth is that knowing the truth is beyond human capacities. They did not question appearances, but only those theories that would seek to explain them as something other than what they appear to be. The Skeptics were especially suspicious of sensory experience, as well as normal teachings of morality.
Plotinus was the primary proponent of the school of thought known as Neoplatonism. These thinkers roughly followed the teachings of Plato, but gave them a decidedly “mystical” twist. Plotinus combined a Platonic description of reality and knowledge, but with a mystical and religious twist. Plotinus saw reality as composed of an hierarchy of levels, like a fountain, with the Divine at the apex and pure matter or nothingness at the bottom. He saw life’s goal to be that of striving for ever higher levels of reality and knowledge.
These were the major schools of philosophical/religious thought between the Greek and the Christian ways of thinking about reality and our knowledge of it, along with how we ought to live accordingly. Many of these emphases, along with the major teachings of Plato and Aristotle, found their way into Medieval thought. Indeed, there are vestiges of each of them still alive within the systems of thought developed by modern and contemporary thinkers.