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Single Idea 16833

[filed under theme 14. Science / C. Induction / 5. Paradoxes of Induction / b. Raven paradox ]

Full Idea

We cannot transform a non-black non-raven into a raven to see whether we get a simultaneous transformation from non-black to black, in the way we can transform a flame without sodium into a flame with sodium.

Clarification

Sodium flames burn yellow

Gist of Idea

We can't turn non-black non-ravens into ravens, to test the theory

Source

Peter Lipton (Inference to the Best Explanation (2nd) [2004], 06 'Unsuitable')

Book Ref

Lipton,Peter: 'Inference to the Best Explanation (2nd ed)' [Routledge 2004], p.98


A Reaction

A white shoe would be an example of a non-black non-raven. People mesmerised by the raven paradox are too concerned with investigation being a 'logical' process. Lipton makes a nice point. We need to know the nature of ravens.


The 16 ideas with the same theme [problem irrelevant evidence for a general law]:

Read 'all ravens are black' as about ravens, not as about an implication [Belnap]
The raven paradox has three disjuncts, confirmed by confirming any one of them [Armstrong]
It is because ravens are birds that their species and their colour might be connected [Harré]
Non-black non-ravens just aren't part of the presuppositions of 'all ravens are black' [Harré]
Contraposition may be equivalent in truth, but not true in nature, because of irrelevant predicates [Harré/Madden]
The items put forward by the contraposition belong within different natural clusters [Harré/Madden]
The possibility that all ravens are black is a law depends on a mechanism producing the blackness [Harré/Madden]
If something in ravens makes them black, it may be essential (definitive of ravens) [Lipton]
My shoes are not white because they lack some black essence of ravens [Lipton]
A theory may explain the blackness of a raven, but say nothing about the whiteness of shoes [Lipton]
We can't turn non-black non-ravens into ravens, to test the theory [Lipton]
To pick a suitable contrast to ravens, we need a hypothesis about their genes [Lipton]
If sentences point to different evidence, they must have different subject-matter [Yablo]
Most people say nonblack nonravens do confirm 'all ravens are black', but only a tiny bit [Yablo]
'All x are y' is equivalent to 'all non-y are non-x', so observing paper is white confirms 'ravens are black' [Mautner, by PG]
Observing irrelevant items supports both 'all x are y' and 'all x are non-y', revealing its absurdity [Schofield,J]