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Single Idea 10660

[filed under theme 9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts ]

Full Idea

Given a prior commitment to cats, a commitment to cat-fusions is not a further commitment. The fusion is nothing over and above the cats that compose it. It just is them. They just are it.

Gist of Idea

A commitment to cat-fusions is not a further commitment; it is them and they are it

Source

David Lewis (Parts of Classes [1991], p.81), quoted by Achille Varzi - Mereology 4.3

Book Ref

'Stanford Online Encyclopaedia of Philosophy', ed/tr. Stanford University [plato.stanford.edu], p.17


A Reaction

I take this to make Lewis a nominalist, saying the same thing that Goodman said about Utah in Idea 10657. Any commitment to cat-fusions being more than the cats, or Utah being more than its counties, strikes me as crazy.

Related Idea

Idea 10657 The counties of Utah, and the state, and its acres, are in no way different [Goodman]


The 35 ideas from 'Parts of Classes'

Sets are mereological sums of the singletons of their members [Lewis, by Armstrong]
Set theory reduces to a mereological theory with singletons as the only atoms [Lewis, by MacBride]
Lewis prefers giving up singletons to giving up sums [Lewis, by Fine,K]
Lewis only uses fusions to create unities, but fusions notoriously flatten our distinctions [Oliver/Smiley on Lewis]
We can build set theory on singletons: classes are then fusions of subclasses, membership is the singleton [Lewis]
We can replace the membership relation with the member-singleton relation (plus mereology) [Lewis]
We can accept the null set, but there is no null class of anything [Lewis]
Classes divide into subclasses in many ways, but into members in only one way [Lewis]
A subclass of a subclass is itself a subclass; a member of a member is not in general a member [Lewis]
We have no idea of a third sort of thing, that isn't an individual, a class, or their mixture [Lewis]
We needn't accept this speck of nothingness, this black hole in the fabric of Reality! [Lewis]
There are four main reasons for asserting that there is an empty set [Lewis]
Atomless gunk is an individual whose parts all have further proper parts [Lewis]
If we don't understand the singleton, then we don't understand classes [Lewis]
If singletons are where their members are, then so are all sets [Lewis]
Set theory has some unofficial axioms, generalisations about how to understand it [Lewis]
Some say qualities are parts of things - as repeatable universals, or as particulars [Lewis]
If singleton membership is external, why is an object a member of one rather than another? [Lewis]
In mereology no two things consist of the same atoms [Lewis]
Maybe singletons have a structure, of a thing and a lasso? [Lewis]
A huge part of Reality is only accepted as existing if you have accepted set theory [Lewis]
To be a structuralist, you quantify over relations [Lewis]
A property is any class of possibilia [Lewis]
Giving up classes means giving up successful mathematics because of dubious philosophy [Lewis]
I like plural quantification, but am not convinced of its connection with second-order logic [Lewis]
Existence doesn't come in degrees; once asserted, it can't then be qualified [Lewis]
Trout-turkeys exist, despite lacking cohesion, natural joints and united causal power [Lewis]
Given cats, a fusion of cats adds nothing further to reality [Lewis]
The one has different truths from the many; it is one rather than many, one rather than six [Lewis]
The many are many and the one is one, so they can't be identical [Lewis]
Set theory isn't innocent; it generates infinities from a single thing; but mathematics needs it [Lewis]
Zermelo's model of arithmetic is distinctive because it rests on a primitive of set theory [Lewis]
Plural quantification lacks a complete axiom system [Lewis]
A commitment to cat-fusions is not a further commitment; it is them and they are it [Lewis]
Lewis affirms 'composition as identity' - that an object is no more than its parts [Lewis, by Merricks]