A tautology's truth is certain, a proposition's possible, a contradiction's impossible. (Certain, possible, impossible: here we have the first indication of the scale that we need in the theory of probability.) (4.464)
About this quote
- What does it mean?
- Logical certainty varies by proposition type.
- In plain terms
- Some statements are certain, others are possible or impossible.
- What can you take from it?
- Recognize degrees of logical certainty.
Where it applies
Putting it to work
Questions to consider
- What is possible vs. certain?
- How do you weigh evidence?
Another view
Real-world certainty is often ambiguous.
More from Ludwig Wittgenstein
It is quite impossible for a proposition to state that it itself is true. (4.442)
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Permalink to quote #19
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