What is the key difference between a fact and an opinion?

The key difference between a fact and an opinion lies in the nature of their truthfulness and verifiability. A fact is defined as a statement that can be objectively proven true or false through evidence or observation. For instance, "The Earth revolves around the sun" is a fact that can be verified through scientific inquiry and empirical data.

In contrast, an opinion is a personal belief or judgment that reflects individual preferences, interpretations, or feelings, and it cannot be universally accepted or proven to be true or false. For example, saying "Chocolate ice cream is the best flavor" expresses a personal preference and cannot be definitively proven or disproven across all individuals.

In summary, the distinguishing characteristic of a fact is its ability to be substantiated with evidence, whereas an opinion reflects an individual's perspective and is subjective in nature.