Extension and Self-Connection

Ben Blumson, Manikaran Singh

DOI: http://dx.doi.org/10.12775/LLP.2021.008


If two self-connected individuals are connected, it follows in classical extensional mereotopology that the sum of those individuals is self-connected too. Since mainland Europe and mainland Asia, for example, are both self-connected and connected to each other, mainland Eurasia is also self-connected. In contrast, in non-extensional mereotopologies, two individuals may have more than one sum, in which case it does not follow from their being self-connected and connected that the sum of those individuals is self-connected too. Nevertheless, one would still expect it to follow that a sum of connected self-connected individuals is self-connected too. In this paper, we present some surprising countermodels which show that this conjecture is incorrect.


mereology; mereotopology; extensionalism; universalism; connection; self-connection

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ISSN: 1425-3305 (print version)

ISSN: 2300-9802 (electronic version)

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