Saturday, October 18, 2008

Scotus on Knowing Individual differences

Back to our regularly scheduled programming. Here is an interesting bit I came across today, regarding the possibility of cognizing our own individual difference. Not entirely clear, and the example about God annihilating one's body and uniting it to another while the soul remains in its original act of intellection is just plain weird and worthy of an analytic philosophical experiment.

Quaestiones super libros Metaphysicorum Aristotelis VII q.13

Differentia individualis a nullo nota est in hac vita communiter. Cuius probatio est: quia tunc nota esset differentia eius ad quodcumque aliud, et ita non posset errare de quocumque alio sibi intellectualiter ostenso quin iudicaret illud esse aliud. Sed hoc est falsum de alio omnino simili nisi tantum de intelligendo se animam et suum actum forte, a quibus differre diceret quantumcumque similia sibi ostensa. De intelligendo tamen se compositum forte erraret quis, si subito Deus suum corpus annihilaret, et aliud suae animae uniret, manente anima in eadem intellectione non interrupta, sic quod anima quantum ad differentiam individualem se ipsam certissime novit 'hoc ens'. Quantum ad naturam specificam, alia, ut sensibilia, certius novit; et hanc notitiam de se inquirit. ... Ergo non possumus individuum definire, non ex parte eius, sed ex impotentia nostra, sicut nec substantias separatas"

The individual difference is commonly known by none in this life, the proof of which is because then its difference to any other would be known, and so it would not be able to err about anything intellectually shown to it that it not judge it to be other. But this is entirely false about any other similar thing unless of understanding itself to be a soul and perhaps its own act, by which it would be said to differ from whatever similar shown to it. Someone would perhaps err in understanding himself to be composite, if God suddenly annihilateed his body and united it to another while at the same time not interrupting the intellection, so that the soul as far as its individual difference most certainly knew itself to be 'this being'. As far as specific nature, it more certainly knows other things, such as sensibiles; at it seeks this knowledge of itself. Therefore we are not able to define the individual, not because of something on the side of the individual, but from our own weakness, just as we cannot define the separated substances.


Ocham said...

Thanks for posting that. I have now got distracted by comparing this question to the one in the Ordinatio, and also to Ockham's discussion of the same question in I D2 q6.

The haecitas bit is literally a few paragraphs on from what you quote above.

Ocham said...

On your point about analytic philosophy, yes. This question and II D3, especially II D3 Q4 (on whether quantity is the individuating principle) are full of fascinating thought experiments where we suppose two individuals are in the same place, or where the same individual is bilocated.

Reminds me of Max Black's thought experiment about the steel spheres rotating in empty space, qualitatively identical.

Another claim by Scotus (in II D3) is about two sunbeams which are qualitively identical but which we can think of as numerically different, which is very similar to something Gareth Evans discussed in the Varieties of Reference 4.1 (p 90).