Wednesday, March 08, 2017

Half a case is not a case

Lunapic Vincent van Gogh version of my walk home

Half-concealed qualification

'The words themselves express a limited claim, but the stress and construction is such that the qualifications are glossed over.' (117).

'There is a fallacy inherent in making a restricted claim and then engaging in it as if were a general claim. (118).

'The fact that the limitation is expressed does not remove the fallacy. It is the fact that the qualification is half-concealed which causes it to be unnoticed, and which excludes relevant information.' (118).

Based on Pirie's definition of this fallacy, limited claims made in premises should only lead to a limited conclusion.

Quizlet

Cited

'Half-Concealed Qualification

the words express a limited claim, but the stress and construction is such that the qualifications are glossed over. ex: "Practically every single case..."'

To avoid fallacy, limited claims, assertions and premises must clearly be described and lead to a limited conclusion.

Half a case (118) is not a case.

The author writes that 'Science and philosophy do not admit unexplained exceptions.' (118).

Explained exceptions are reasonable when presented as limited premises leading to a limited conclusion.

From (119)

Palm trees do not grow in England, so these must be a different type of tree.

Pirie points out there are exceptions.

It would be reasonable to state that typically palm trees do not grow in England, but there are exceptions.

From (119)

Just about every Cambridge man from the foreign office in the 1940s was a spy. Fire them all.

In reality it was only a few of these Cambridge men that were spies.

This should be presented as a limited statement, not a general one.

The fact that half a case is not a case means that a limited premise needs to be identified as such and not presented as a general premise.

PIRIE, MADSEN (2006)(2015) How To Win Every Argument, Bloomsbury, London.