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Twelve Principles of Knowledge

George Dunseth outlines basic principles for knowing whether or not ideas are true.

As I began to think and exchange ideas I soon realised that it is important to be reasonable and rational. But I then felt a powerful need to understand what that means. And so I began making a lifelong, constantly revised, simple list of how all of us support our truth claims.

What counts as evidence for truth in rational argument? I have attempted to be simple, clear and exhaustive. These principles can be printed on a piece of paper and posted proudly on your refrigerator. They apply both to the sciences and the humanities, since science does not have a monopoly on reason.

None of the principles are sufficient in themselves, and some are clearly stronger and more warranted than others. The more of them that apply to your claim, the more warranted your truth claim is – we could even say, the more reasonable it is.


1. Non-Contradiction: Is this idea or set of ideas consistent, and therefore coherent? This is the first principle of formal logic.

2. Observation: Is this idea verified by sense observation?

3. Experimentation: Can this observation be repeated predictably?

4. Testability: Is this idea in theory falsifiable, and can its truth value be put to the test? In other words, is it possible to think about this truth claim being wrong?

5. Comprehensiveness: That which explains the most. Is this the simplest explanation of the most phenomena?

6. Fit: Does this help a lot of related factors fit nicely into place?

7. Pragmatism: What works best? Does this work? If a set of ideas works, then it is likely that there is something true about them!

8. Intuition: Does this idea strongly inwardly demand assent?

9. Common Sense: Is this very widely, or perhaps almost universally, accepted as true? (Many philosophers cringe here, but may I suggest that a little regard for common sense is not unhelpful?! And like all the principles, it cannot stand alone.)

10. History & Tradition: Does this have historical warrant – meaning that it has stood the test of time?

11. Warranted Authority: Is this backed by a reliable testimony or source?

12. Analogy: Does this idea cohere with a related idea which is seen to be true? Then this similarity could imply its own truth.

Finally, a word on ‘mystical’ truth claims. Mystical experience is not in the above twelve principles of reason, since by definition conclusions based on it are not thereby supported by reason. However, I think it is wise to be open to the idea that there may be truths inaccessible to reason or outside its parameters.

© George Dunseth 2018

George Dunseth is a jazz musician in Leicester, England.

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