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Single Idea 18894

[filed under theme 5. Theory of Logic / E. Structures of Logic / 7. Predicates in Logic ]

Full Idea

We organise our concepts of predicability on a hierarchical tree. At the top are terms like 'interesting', 'exists', 'talked about', which are predicable of anything. At the bottom are names, and in between are predicables of some things and not others.

Gist of Idea

Predicates form a hierarchy, from the most general, down to names at the bottom

Source

Fred Sommers (Intellectual Autobiography [2005], 'Category')

Book Ref

'The Old New Logic', ed/tr. Oderberg,David S. [MIT 2005], p.3


A Reaction

The heirarchy seem be arranged simply by the scope of the predicate. 'Tallest' is predicable of anything in principle, but only of a few things in practice. Is 'John Doe' a name? What is 'cosmic' predicable of? Challenging!


The 10 ideas from Fred Sommers

'Predicable' terms come in charged pairs, with one the negation of the other [Sommers, by Engelbretsen]
Sommers promotes the old idea that negation basically refers to terms [Sommers, by Engelbretsen]
Translating into quantificational idiom offers no clues as to how ordinary thinkers reason [Sommers]
Predicates form a hierarchy, from the most general, down to names at the bottom [Sommers]
Truthmakers are facts 'of' a domain, not something 'in' the domain [Sommers]
Logic which maps ordinary reasoning must be transparent, and free of variables [Sommers]
Unfortunately for realists, modern logic cannot say that some fact exists [Sommers]
In standard logic, names are the only way to refer [Sommers]
Predicate logic has to spell out that its identity relation '=' is an equivalent relation [Sommers]
Categories can't overlap; they are either disjoint, or inclusive [Sommers, by Westerhoff]