What is the difference between a tautology and a truism?

The difference between a tautology and a truism lies in their definition and use context:

  • A tautology is a statement that repeats the same idea using different words, which makes it logically redundant. For example, “free gift.”
  • A truism is a self-evident and widely accepted statement that adds little or no value to a discussion because it does not provide any new or interesting information. For example, “What goes around comes around.”

In short, a tautology involves redundancy or logical repetition, while a truism states an obvious truth that lacks depth or new information.