How do you distinguish pertinent from peripheral facts?

To distinguish pertinent from peripheral facts, focus on the relevance of the information to the main issue or topic at hand. Pertinent facts directly support or clarify key arguments, while peripheral facts may provide background or context but do not directly influence the core discussion. Assess the significance of each fact in relation to the desired outcome or understanding, prioritizing those that enhance comprehension or decision-making. Lastly, consider the audience's needs, as what may be peripheral to one might be pertinent to another.