Explanatory regress and mechanistic explanation of the Small by the Big

1. Explanatory regress and mechanistic explanation of the Smallby theBig Phyllis McKay Illari University of Kent

2. Explanatory Regress 1 The usual problem

3. Gap-o-phobia

4. Gap-o-phobia

5. Gap-o-phobia

6. Gap-o-phobia ?

7. Gap-o-phobia ? HELP! I fell out of the bottom of the world!

8. Problem of explanatory regress • We cannot seem to evade the possibility of just such ‘gaps’ at the fundamental level. ?

9. Problem of explanatory regress • We cannot seem to evade the possibility of just such ‘gaps’ at the fundamental level. • Physical theory might even be telling us that such ‘gaps’ actually do exist. ?

10. Glennan ‘some interactions between parts cannot be explained by the operation of mechanisms. For instance, two electrons might interact with each other, but there is no mechanism connecting them. If mechanical interactions are truly causal, the fundamental interactions on which they ultimately depend must be causal as well, so a complete causal theory requires a theory of fundamental causal interactions.’ Routledge Encyclopaedia 2008

11. Stathis throws down the gauntlet! • ‘I take this to be a crucial problem of the mechanistic approach. In a sense, this approach fills in the 'chain' that connects the cause and the effect with intermediate loops. But there is still no account of how the loops interact. Here, it might well be the case that the most general and informative thing that can be said about these interactions is that there are relations of counterfactual dependence among the parts of the mechanism.’ (Psillos 2004 p314-5.)

12. Explanatory Regress 2 What Explanation?

13. Epistemic and Ontic Well-known distinction: • Ontic mechanistic explanation about the worldly producer of the phenomena. • In this sense the mechanism itself explains. • Epistemic mechanistic explanation about the phenomenon being rendered intelligible to an inquirer. • In this sense the description or the act of describing the mechanism explains.

14. Epistemic and Ontic ‘Productive continuities are what make the connections between stages intelligible. ... A missing arrow, namely, the inability to specify an activity, leaves an explanatory gap in the productive continuity of the mechanism.’(MDC p3.) • Unfortunate mingling of ontic and epistemic.

15. ‘Where are the little bits?’ • We want explanations in terms of little bits. • Psychologically, we like them. • But this is no reason to believe little bits will always be available. • Particularly not in mind-bending fields such as QM. • (Effective explanations will still require attention to epistemic aspects such as effective diagrams, equations, models.)

16. Want ontic explanation • Keep clearer that we are attempting to describe how the world is. • Worldly production of phenomena • Might not fit our idea of what counts as a fundamental explanation, or cause. • If there aren’t littler bits in some cases, then there aren’t. And wishing won’t make it so.

17. Ontic explanation: the competitors ?

18. Ontic explanation: the competitors ? Capacities • Blob has a capacity to produce blob Capacity

19. Ontic explanation: the competitors ? Capacities • Blob has a capacity to produce blob Laws • It’s a law of nature that says blob then blob Capacity

20. Well-known problems Laws • It’s a law of nature that says blob then blob Capacities • Blob has a capacity to produce blob Objections • ‘Dormitive virtue’ Capacity

21. Well-known problems Laws • It’s a law of nature that says blob then blob Capacities • Blob has a capacity to produce blob Objections • ‘Dormitive virtue’ Capacity • ‘I don’t care what’s happening elsewhere!’

22. Really do want a mechanism • Activities and entities • Organized so as to produce the phenomenon Broadly involves both • Things and their properties • Generalisations describing their interactions

23. Really do want a mechanism • Activities and entities • Organized so as to produce the phenomenon Broadly involves both • Things and their properties • Generalisations describing their interactions ‘Together we’re better!’

24. Explanatory regress 3 What Regress?

25. Traditional conception of mechanistic explanation Reductive • Behaviour of higher-level explained by behaviour of parts Locally supervenient • Behaviour of whole supervenes on that of local parts Big by small • Little bits explain the big

26. Traditional conception of mechanistic explanation Reductive • Behaviour of higher-level explained by behaviour of parts. Locally supervenient • Behaviour of whole supervenes on that of local parts. Big by small • Little bits explain the big. • Undermined by emergence, autonomy. • Undermined by importance of context – system biology. • I will examine this.

27. Bechtel (2008) and Craver (2007) • In constructing a mechanistic explanation, you look for the working parts. • Not everything in the area counts as a working part. • You look experimentally: • Briefly, you wiggle putative components, look for alteration in phenomenon, and vice versa. • To an extent it is arbitrary what you treat as part of the mechanism, what you treat as external. (Craver’s part-whole criterion.)

28. Darden (Phil Sci 2008) • ‘Often biologists engage in much investigative work to discover the levelat which a given mechanism operates. Geneticists worked to find theoperative level for genetic linkage, ruling out the coupling of paired allelesand the reduplication of germ cells and ruling in chromosomal mechanisms (Darden 1991). Genes are linked because they ride along on chromosomes in meiotic mechanisms. In immunology, the working entities inclonal selection were at first hypothesized to be self-replicating proteinmolecules but were later found to be self-reproducing immune cells (Darden 2006, Chapter 8). These two examples show that biologists do notalways discover working entities in mechanisms by going to a smaller sizelevel; sometimes the operative units are intermediate or larger than at firsthypothesized: not genes but chromosomes, not molecules but cells.’ (961)

29. Darden Case 1 • ‘Often biologists engage in much investigative work to discover the levelat which a given mechanism operates. Geneticists worked to find theoperative level for genetic linkage, ruling out the coupling of paired allelesand the reduplication of germ cells and ruling in chromosomal mechanisms (Darden 1991). Genes are linked because they ride along on chromosomes in meiotic mechanisms. In immunology, the working entities inclonal selection were at first hypothesized to be self-replicating proteinmolecules but were later found to be self-reproducing immune cells (Darden 2006, Chapter 8). These two examples show that biologists do notalways discover working entities in mechanisms by going to a smaller sizelevel; sometimes the operative units are intermediate or larger than at firsthypothesized: not genes but chromosomes, not molecules but cells.’ (961)

31. Darden Case 2 • ‘Often biologists engage in much investigative work to discover the levelat which a given mechanism operates. Geneticists worked to find theoperative level for genetic linkage, ruling out the coupling of paired allelesand the reduplication of germ cells and ruling in chromosomal mechanisms (Darden 1991). Genes are linked because they ride along on chromosomes in meiotic mechanisms. In immunology, the working entities inclonal selection were at first hypothesized to be self-replicating proteinmolecules but were later found to be self-reproducing immune cells (Darden 2006, Chapter 8).These two examples show that biologists do notalways discover working entities in mechanisms by going to a smaller sizelevel; sometimes the operative units are intermediate or larger than at firsthypothesized: not genes but chromosomes, not molecules but cells.’ (961)

32. SO: When you look for the working parts, sometimes they are not the little bits.

33. Explanatory regress 4 Positive story

34. Glennan ‘some interactions between parts cannot be explained by the operation of mechanisms. For instance, two electrons might interact with each other, but there is no mechanism connecting them. If mechanical interactions are truly causal, the fundamental interactions on which they ultimately depend must be causal as well, so a complete causal theory requires a theory of fundamental causal interactions.’ Routledge Encyclopaedia 2008

35. Gap-o-phobia therapy? Interesting question: • not about the fundamental level • not about what the fundamental explainers are • not about causation (or anything else!) draining out of the bottom of the world Real question is about causalconnection.

36. Glennan ‘some interactions between parts cannot be explained by the operation of mechanisms. For instance, two electrons might interact with each other, but there is no mechanism connecting them. If mechanical interactions are truly causal, the fundamental interactions on which they ultimately depend must be causal as well, so a complete causal theory requires a theory of fundamental causal interactions.’ Routledge Encyclopaedia 2008

37. Gap-o-phobia therapy? Interesting question: • not about the fundamental level • not about what the fundamental explainers are • not about causation (or anything else!) draining out of the bottom of the world Real question is about causalconnection. Now we can ask: If the big can explain the small what then should we think about causal (and mechanistic) connection?

39. Productive continuity • Machamer, Bogen, Darden still worrying about productive continuity– which is causal connection. • All mechanisms ‘...have productive continuity from one stage to the next…[such that] entities and activities of one stage give rise to the next stage…but few mechanisms have information flow through multiple stages of the [operation of the] mechanism.’ • Machamer and Bogen (CitS volume) quoting Darden (2006 p. 283), on the issue they address.

40. Stathis’ gauntlet! • ‘I take this to be a crucial problem of the mechanistic approach. In a sense, this approach fills in the 'chain' that connects the cause and the effect with intermediate loops. But there is still no account of how the loops interact. Here, it might well be the case that the most general and informative thing that can be said about these interactions is that there are relations of counterfactual dependence among the parts of the mechanism.’ (Psillos 2004 p314-5.)

41. Stathis’ gauntlet! • ‘I take this to be a crucial problem of the mechanistic approach. In a sense, this approach fills in the 'chain' that connects the cause and the effect with intermediate loops. But there is still no account of how the loops interact. Here, it might well be the case that the most general and informative thing that can be said about these interactions is that there are relations of counterfactual dependence among the parts of the mechanism.’ (Psillos 2004 p314-5.) • The most general and informative thing that can be said about these interactions will be in the relevant scientific theory – perhaps QM. • Any account of how the loops interact will also be in QM. The surprising thing: quantum non-locality suggests we have to look UP, not down, for these stories.

42. Objection ‘Then mechanistic explanation is really at bottom laws-explanation!’ • Something at the ‘bottom’ doesn’t make mechanisms ‘really’ anything! Either • a) QM theory in some sense continuous with mechanistic explanation: very interesting. • b) QM very different: the interface will be very important. • Either way, we are now asking a more precise, and more fruitful, question.

47. ‘We also believe it to be likely, although we cannot argue for it here, that what we take to be intelligible is a product of the ontogenicand phylogenetic development of human beings in a world such as ours.’ MDC p22

48. MDC P23 ‘Higher-level entities and activities are thus essential to the intelligibility of those at lower levels, just as much as those at lower levels are essential for understanding those at higher levels. It is the integration of different levels into productive relations that renders the phenomenon intelligible and thereby explains it.’

49. Machamer 2004 p31 in section discussing necessity ‘Metaphysically, activities are what do the ruling out, by connecting one entity through its actions to another entity or activity or by producing a change in another entity. In this way activities function as selective processes: they are explanations of the arrows in the cartoon diagrams, and spell out how the previous stage or situation produces this certain result rather than some other. In other words, among all the changes that might have occurred at the next stage, this one did occur because of the activity that produced it.’

50. Machamer and Bogen paper for our volume: MDC ‘…exhibit productive continuity without gaps from the set-up to termination conditions. Productive continuities are what make the connection between stages intelligible. (Machamer, Darden and Craver [2000] p. 3)’