Final answer:
The two main groups of rational thinkers are the Socratic and Aristotelian followers, influenced by the teachings of Socrates and Aristotle. They were core figures in classical Greek philosophy, focusing on different aspects of understanding the world.
Step-by-step explanation:
The two main groups of rational thinkers referred to in the question are, indeed, Aristotelian and Socratic philosophers. These groups reflect the influences of Aristotle and Socrates, respectively. Based on the provided information, we can deduce that the thinkers of the Pre-Socratic era engaged in different areas of inquiry, which included the naturalistic and metaphysical interpretations of the universe. It's important to note that in classical Greek philosophy, Socrates, Plato, and Aristotle are considered to be the central figures, with Aristotle and Plato having distinct philosophies which were later integrated into various systems of thought, including Christianity. The ideal system of government, according to Plato, as indicated by the review question, is rule by philosophers. This clearly outlines the influence of these thinkers and underscores the distinction between the two groups mentioned in the original question, bringing the correct answer to be D) Socratic and Aristotelian followers.