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Ideas for 'Necessary Existents', 'A Structural Account of Mathematics' and 'Intro to Gdel's Theorems'

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8. Modes of Existence / A. Relations / 4. Formal Relations / c. Ancestral relation

10617	The 'ancestral' of a relation is a new relation which creates a long chain of the original relation [Smith,P]
	Full Idea: The 'ancestral' of a relation is that relation which holds when there is an indefinitely long chain of things having the initial relation.
	From: Peter Smith (Intro to Gödel's Theorems [2007], 23.5)
	A reaction: The standard example is spotting the relation 'ancestor' from the receding relation 'parent'. This is a sort of abstraction derived from a relation which is not equivalent (parenthood being transitive but not reflexive). The idea originated with Frege.