In an earlier post, “How Can We Gain Knowledge” (May 2020), I argued that the primary, if not only, way we can justify our knowledge or belief is by the evidence that supports the knowledge or belief. However not all evidence is of equal worth, so what makes some evidence better than others.
- Confirmability: if the evidence is confirmable by say repetition as in a scientific experiment, or from other sources, it will be more supportive of the knowledge or belief.
- Multiple Sources: If there is but one source for a piece of evidence, then it is less compelling than if the piece of evidence comes from many sources.
- Authority: If the evidence is from a source with knowledge and hence authority, as in a senior scientist who has spent a lifetime studying the subject, then it is again more compelling than if the source has no real authority on the subject.
- Falsifiability: Can the evidence be tested and shown to be wrong, at least in principle. If not this is weaker than evidence that can be tested and so is falsifiable.
- Multiple Evidences: If there are many differing evidences to support the knowledge or belief then this will be better support than if there is only one piece of evidence.
- Independent Deep Evidence Chains: An evidence statement is really just another piece of knowledge so needs to be supported by its own evidence base and so on. Thus if the evidence chains are deep and independent then this will be more compelling.
- Coherent Evidence: If multiple sources of evidence are coherent with one another rather than conflict with one another then they will be more convincing.
- Correspondent Evidence: If the evidence corresponds to our understanding of the “real world” then it will again be more compelling than if it is at odds with that understanding.
Thus we can now assess any evidence that may be presented in support of any knowledge or belief and help to determine our personal position on the truth of any knowledge or belief.