more from this thinker     |     more from this text


Single Idea 13458

[filed under theme 4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets ]

Full Idea

A partial ordering is a 'total ordering' just in case any two members of its field are comparable, that is, either a is R to b, or b is R to a, or a is b.

Gist of Idea

A partial ordering becomes 'total' if any two members of its field are comparable

Source

William D. Hart (The Evolution of Logic [2010], 1)

Book Ref

Hart,W.D.: 'The Evolution of Logic' [CUP 2010], p.23


A Reaction

See Idea 13457 for 'partial ordering'. The three conditions are known as the 'trichotomy' condition.

Related Idea

Idea 13457 A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD]


The 10 ideas with the same theme [ordered sets, and using sets to describe orderings]:

Order rests on 'between' and 'separation' [Russell]
Order depends on transitive asymmetrical relations [Russell]
The ordered pair <x,y> is defined as the set {{x},{x,y}}, capturing function, not meaning [Gupta]
'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD]
A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD]
A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD]
Von Neumann defines α<β as α∈β [Hart,WD]
'Well-ordering' of a set is an irreflexive, transitive, and binary relation with a least element [Shapiro]
A collection is 'well-ordered' if there is a least element, and all of its successors can be identified [Lavine]
Ordinals play the central role in set theory, providing the model of well-ordering [Walicki]