This article, https://www.ft.com/content/c2ebbbf7-09bd-493e-b021-e7bad04f8fa7, is a brief review of this book: https://www.amazon.co.uk/What-Intelligence-Evolution-Computing-Antikythera/dp/0262049953
The reviewer asks a question that I assume is planted in the book as a conundrum to deal with the questions : “Who am I”? or “Where is my intelligence located?”:
“What happens when all the components of Theseus’s ship are gradually replaced over time? Is the rebuilt boat, containing none of its original parts, still the ship of Theseus?”
The issue with this conundrum, and its answers, is that it never factors in time. There seems to me to be a major difference between the gradual replacement of parts of an object, or in the main test case, the replacement of our body’s constituent elements as we grow and metabolise, and a sudden or all-at-once replacement
The difference lies in the gradual replacement of parts versus the replacement of the whole. For the former, adaption is possible, for the latter less so. (A further dimension may be the complexity and scale of the entity or organism being replaced.)
I am still the ‘same’ person today as I was at 20 years old because while my physical body has replaced itself at the cellular level this has been gradual, piecemeal, not catastrophic. In the case,too, of a conscious, feeling entity this replacement is adaptive.
But I cannot survive a catastrophic replacement – if I am blown up, or in some dramatic way may body ceases to function, ‘I’ cannot adapt to the change.
This is not a conundrum but common sense.
Take the contrasting example of Trigger’s Broom, used for comedic effect in ‘Only Fools and Horses’. Trigger, a road sweeper, is rewarded with a medal by his local council for still having the same broom after 20 years service. The medal is because he has helped save the council money by only using one broom. His incredulous friends ask how this is possible. “It’s not the same broom!” his friends incredulously reply. “But I look after it well …” replies Trigger, “this broom has had 17 new heads and 14 new handles.”
The absurdity of this ‘entity replacement’ joke is that of course with only two components it is simple to see that it is not the same broom that Trigger started out with. It has the same shape, the same form, but the parts are ostensibly not original. The broom has the same form but its parts are not the original ones.
But as the complexity of an entity grows so we can confidently argue that it is the same entity even as parts are replaced. Even Theseus’s ship is too complex for us to say which components render it original and which render it a replacement. And the same goes for the human body, and with it the mind.