1 SNAP and SPAN Barry Smith

2 Two categories of entities Substances and processes Continuants and occurrents In preparing an inventory of reality we keep track of these two different categories of entities in two different ways

3 Snapshot vs. Video substance t i m e process

4 SNAP vs SPAN substance t i m e process

5 The SNAP Ontologies t1t1 t3t3 t2t2 here time exists outside the ontologies, as an index or time-stamp

6 each section through reality includes everything which exists at the corresponding now titi

7 nothing temporally extended is visible in a SNAP ontology titi

8 here time exists as part of the domain of the ontology The SPAN Ontology

9 and only what is temporally extended is visible The SPAN Ontology

10 SNAP = a succession of ontologies of entities which do not have temporal parts The first 5-minute phase of my existence is not a temporal part of me It is a temporal part of that complex process which is my life

11 SPAN = an ontology of processes, of entities which have temporal parts The first 5 minutes of my headache is a temporal part of my headache

12 So let’s have both

13 Not: Perdurantism vs. Endurantism but SNAP and SPAN … how to have your ontological cake and eat it too

14 you titi

15 t i m e your life

16 Qualities, dispositions, powers, plans, roles, functions belong to the SNAP ontology The realizations of dispositions, powers, plans, roles, functions belong to the SPAN ontology

17 How to orient the “Sixteen Days argument in relation to SNAP and SPAN?

18 Proposal: This story

19 is a SNAP story – it is a story which can be told only by referring to entities in the category of substance existing at different times

20 Daniel’s charge: (Q1) When does a human being begin to exist? (Q2) At what stage is the foster first transtemporally identical to the humanbeing as it exists after birth? are not the same question

21 Why not? because there are accounts of human beings (by Perry, Quine …) which deny transtemporally identical (enduring) substances they talk instead in terms of stages

22 but such accounts rest upon a confusion of SNAP with SPAN since they see the sum of stages as a human being rather than as the life of a human being thus they see the former as having temporal parts

23 Hence it is still admissible to answer (Q1) When does a human being begin to exist? by answering (Q2) At what stage is the foster first transtemporally identical to the humanbeing as it exists after birth?

24 But don’t we then need to give conditions for transtemporal identity? No Quine’s “No entity without identity” = No entity without an identity criterion confuses epistemology with ontology Compare: no truth without a truth criterion

25 Quine can believe his own slogan only because he believes that all entities, including human beings, are in any case the mere products of gerrymandering (they are the products of our imposing identity criteria on some I know not what)

26 Question: When does a human being begin to exist? Answer: it’s all just a matter of convention … because everything is a matter of convention

27 Another tack I say "It seems difficult to conceive of any abrupt threshold associated with the transition to consciousness that would constitute a substantial change in the organism considered as a whole."

28 Daniel says: There are two problems here: 1.a baldness problem 2.a death problem

29 1. the baldness problem Daniel: “The fact that there is no abrupt threshold does not keep us from drawing a sharp boundary somewhere at will.” conventionalism again… conventionalism can cut no ontological ice!

30 2. the death problem I say: the transition to personhood cannot be a substantial change because it involves a change in only part of the substance in question (roughly: the brain and nervous system)

31 But surely A substantial change in a part of us, namely in the brain, can determine that substantial change which is the end of our existence.

32 a possible response the arguments for the brain death criterion are explicitly ethical arguments – not clear that they have relevance for our, ontological purposes ontological considerations force us to insist on the total body death criterion

33 duality is sustained a substantial change occurs – an instantaneous change in the whole of the human individual – both at the beginning and at the end of the life of the individual