Final answer:
The key difference between Sophists and Ionian philosophers lies in the former's focus on rhetoric and relative truths aimed at personal success, while the latter pursued objective, rational explanations for natural phenomena. Plato and Aristotle later engaged with both schools of thought critically.
Step-by-step explanation:
The Sophists and Ionian philosophers were both influential groups in ancient Greek culture, but they differed significantly in their approaches to knowledge and education. The Sophists were known for their skills in rhetoric and their belief that truth was relative, emphasizing individual success and the ability to argue any position persuasively. They offered their services for a fee, teaching skills valuable in public life, particularly in law and politics.
In contrast, the Ionian philosophers, sometimes referred to as pre-Socratic philosophers, were more interested in pursuing natural explanations for the workings of the universe, free from myth and supernatural intervention. They sought objective truths and were driven by curiosity and rational inquiry rather than the practical application of knowledge for personal gain. Plato and later Aristotle would refine and challenge the approaches of both, with particular criticism aimed at the Sophists for their perceived indifference to the absolute truth.