Which class of evidence is considered the most certain?

Primary evidence is regarded as the most certain class of evidence because it refers to original documents or firsthand accounts that are directly related to the matter at hand. This type of evidence provides the most reliable information because it has not been altered or interpreted; it serves as the original source.

For example, in legal contexts, primary evidence might include original contracts, deeds, or testaments, which directly establish the facts in dispute. The reliability of primary evidence stems from its authenticity and the fact that it does not rely on any intermediary interpretations, making it the strongest form of support for an argument or claim.

In contrast, other classes such as secondary evidence, which includes copies or summaries of documents, can be subject to discrepancies and interpretations that might lead to inaccuracies. Direct evidence and extrinsic evidence have their own specific contexts and uses but do not carry the same level of inherent reliability as primary evidence.