Conatus: REVISED EDITION by Tom Wallace - HTML preview

C O N A T U S

We are ambiguous about the ship of Theseus because — on the one hand — a ship has a certain identity as a complex thing. On the other hand, a ship is just a collection of material parts, which could, in theory, be replaced with complete correspondence.

Is there a similar ambiguity with a person? If all our body parts were replaced by robotics then would we be the same person? Probably a provisional yes, if the brain is intact. But what if the brain itself is slowly replaced by electronics? Would there be a point where consciousness would simply stop? Or would our whole sense of self continue all the way to the whole body and brain being replaced?

There is still a bit of a gap though between identity of the sort we have been describing — that is, just being a unique thing — and identity in terms of consciousness. The examples given of a country, a ship and a person are all points on a scale between simple identity and identity that we might describe as essence — something that seems to make a unique character or persona. Consciousness is perhaps an emergent quality that produces this latter type of identity. It is doubtful if replacing the body parts of people with parts of different substances — or even the same substances — would even allow consciousness to emerge — let alone be the same consciousness — the same person.

Descartes, rather strangely, suggested that it is duration in time that marks out a substance as having an essence. This aspect of essence I left out of earlier chapters, as its importance really only starts to come to the fore when we are

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