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Single Idea 15285

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

Full Idea

If empirical predicates are linked in clusters, contraposition of (black, raven) would carry one via such pairs as (shoe, white) into a different empirical cluster, or no cluster at all.

Clarification

A→B so ¬B→¬A is contraposition

Gist of Idea

The items put forward by the contraposition belong within different natural clusters

Source

Harré,R./Madden,E.H. (Causal Powers [1975], 7.I)

Book Ref

Harré,R/Madden,E.H.: 'Causal Powers: A Theory of Natural Necessity' [Blackwell 1975], p.124

A Reaction

This is, of course, addressed to Hempel's Raven Paradox. Those paradoxes now strike me as relics of a time when Humean empiricism and logic were thought to be the best approaches to scientific theory. Harré and Madden pioneered a better view.

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

19000 Read 'all ravens are black' as about ravens, not as about an implication [Belnap]
17674 The raven paradox has three disjuncts, confirmed by confirming any one of them [Armstrong]
15889 It is because ravens are birds that their species and their colour might be connected [Harré]
15890 Non-black non-ravens just aren't part of the presuppositions of 'all ravens are black' [Harré]
15284 Contraposition may be equivalent in truth, but not true in nature, because of irrelevant predicates [Harré/Madden]
15285 The items put forward by the contraposition belong within different natural clusters [Harré/Madden]
15287 The possibility that all ravens are black is a law depends on a mechanism producing the blackness [Harré/Madden]
16832 If something in ravens makes them black, it may be essential (definitive of ravens) [Lipton]
16836 My shoes are not white because they lack some black essence of ravens [Lipton]
16831 A theory may explain the blackness of a raven, but say nothing about the whiteness of shoes [Lipton]
16833 We can't turn non-black non-ravens into ravens, to test the theory [Lipton]
16834 To pick a suitable contrast to ravens, we need a hypothesis about their genes [Lipton]
18993 If sentences point to different evidence, they must have different subject-matter [Yablo]
19003 Most people say nonblack nonravens do confirm 'all ravens are black', but only a tiny bit [Yablo]
4782 '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]
7006 Observing irrelevant items supports both 'all x are y' and 'all x are non-y', revealing its absurdity [Schofield,J]