DOI: 10.4324/9780415249126-N040-1
Version: v1,  Published online: 1998
Retrieved September 22, 2021, from

5. Particulars as aggregates

Emergentism is the doctrine that something new emerges or comes into being when materials come together and take the form of something with a kind of unity and persistence across time, as for instance a living being. Such a thing is constituted by a plurality of parts, but is something distinct from just the aggregate of those parts.

The distinction between a thing and the aggregate of its parts can be drawn by reference to their logical independence: you could have had either one without the other. Consider a particular ship, say the ship of Theseus. This ship is constituted by planks of wood. But the planks could have existed without ever constituting a ship; and the ship could have been constituted by different planks. Hence the ship is not the same thing as the aggregate of the planks which constitute it.

This conception of an individual as something other than just the aggregate of its parts has been bedevilled by a puzzle, famously described by Hobbes (Molesworth 1837–45 (4): 135; the example traces back to Plutarch’s ‘Life of Theseus’ §§22–3). Suppose that, over time, worn planks on the ship of Theseus are replaced by new ones, and a working ship is maintained in continuous existence; meanwhile, the worn planks which are taken away are gradually reassembled in just the way they were arranged in the original ship. One principle leads us to say that the working ship with new planks is the ship of Theseus; another principle leads us to say that the reassembled ship with worn planks is the ship of Theseus. Yet an individual ship cannot be in two places at once: which of them is the ship of Theseus? This ship puzzle can be paralleled by puzzles of personal identity across time (see Personal identity).

Objections of this sort have been raised against the theory that there are particulars which have parts, but which are not just the aggregates of those parts (the contrary theory takes all particulars to be just the aggregates of their parts). Goodman and Quine (1947) have been very influential in promoting the idea that particulars are best understood through the theory of the part–whole relation, or mereology (see Mereology). Furthermore, according to Goodman, Quine and others, an individual which persists through some interval of time has distinct parts existing at each distinct time in that interval. Among the things which exist at one time is a timeslice which exists only at that time; among the things which exist at another time is a different timeslice; the thing which exists across several distinct times is just an aggregate of distinct timeslices.

Hobbes’ puzzle question, ‘Which is the ship of Theseus?’, is then diagnosed as turning upon a merely verbal vagueness. There are two distinct aggregates which are broadly ship-shape, and it is mere semantic indeterminacy which makes us unsure as to which of them should be called ‘the ship of Theseus’. Similar reasoning applies equally to persons.

Citing this article:
Bigelow, John C.. Particulars as aggregates. Particulars, 1998, doi:10.4324/9780415249126-N040-1. Routledge Encyclopedia of Philosophy, Taylor and Francis,
Copyright © 1998-2021 Routledge.

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