Quote by Miguel de Unamuno
When a thing is said to be not worth refuting you may be sure that either it is flagrantly stupid -- in which case all comment is superfluous -- or it is something formidable, the very crux of the problem.
Summary
This quote suggests that when an idea or argument is dismissed as not worthy of refutation, it typically falls into one of two categories: it is either blatantly foolish, making any response unnecessary, or it is an idea that poses a significant challenge and lies at the heart of the issue being discussed. In the latter case, not engaging with the argument may indicate the difficulty or complexity of the problem being addressed. The quote implies that in order to understand and address important issues, one must be willing to engage with formidable ideas, rather than dismissing them outright.