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Single Idea 13411

[filed under theme 6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers ]

Full Idea

If we accept the Frege-Russell analysis of number (the natural numbers are the cardinals) as basic and correct, one thing which seems to follow is that one could know, say, three, seventeen, and eight, but no other numbers.

Gist of Idea

If numbers are basically the cardinals (Frege-Russell view) you could know some numbers in isolation

Source

Paul Benacerraf (Logicism, Some Considerations (PhD) [1960], p.164)


A Reaction

It seems possible that someone might only know those numbers, as the patterns of members of three neighbouring families (the only place where they apply number). That said, this is good support for the priority of ordinals. See Idea 13412.

Related Idea

Idea 13412 Obtaining numbers by abstraction is impossible - there are too many; only a rule could give them, in order [Benacerraf]


The 19 ideas with the same theme [which type of numbers is the most fundamental?]:

One is prior to two, because its existence is implied by two [Aristotle]
God made the integers, all the rest is the work of man [Kronecker]
Dedekind defined the integers, rationals and reals in terms of just the natural numbers [Dedekind, by George/Velleman]
Ordinals can define cardinals, as the smallest ordinal that maps the set [Dedekind, by Heck]
Order, not quantity, is central to defining numbers [Dedekind, by Monk]
Cantor took the ordinal numbers to be primary [Cantor, by Tait]
Quantity is inconceivable without the idea of addition [Frege]
Could a number just be something which occurs in a progression? [Russell, by Hart,WD]
Some claim priority for the ordinals over cardinals, but there is no logical priority between them [Russell]
Ordinals presuppose two relations, where cardinals only presuppose one [Russell]
Properties of numbers don't rely on progressions, so cardinals may be more basic [Russell]
Von Neumann treated cardinals as a special sort of ordinal [Neumann, by Hart,WD]
Addition of quantities is prior to ordering, as shown in cyclic domains like angles [Dummett]
Ordinals seem more basic than cardinals, since we count objects in sequence [Dummett]
If numbers are basically the cardinals (Frege-Russell view) you could know some numbers in isolation [Benacerraf]
Benacerraf says numbers are defined by their natural ordering [Benacerraf, by Fine,K]
A cardinal is the earliest ordinal that has that number of predecessors [Bostock]
One could grasp numbers, and name sizes with them, without grasping ordering [Wright,C]
The natural numbers are primitive, and the ordinals are up one level of abstraction [Friend]