Ep. 339: Brian Ellis on the Metaphysics of Science (Part One)

0:00 Mark: Foreign. To the Partially Examined Life, a podcast by some guys who at one point set on doing philosophy for a living, but then thought better of it. Our question for episode 339 is something like what metaphysics should underlie modern science. We read chapters one through four of Brian Ellis's 2002 book, the Philosophy of Nature, A Guide to the New Essentialism. For more information about the book and the podcast, please see partiallyexaminedlife.com this is Mark Linsenmayer, a passivist, but not a pacifist in Madison, Wisconsin.

0:37 Seth: This is Seth Paskin recording from Austin, Texas. In this possible world or the actual world decide at the end of the show.

0:48 Wes: This is Wes Alwan, a gene identical microspecies in a natural kind cluster in Cambridge, Massachusetts.

0:57 Christopher: And this is Christopher Heath. I am performing a cost benefit analysis on my ontological commitments in North Hollywood, California.

1:05 Mark: Welcome back, Chris.

1:07 Christopher: Thanks. Good to be back.

1:09 Mark: We sometimes tag Chris for our Philosophy of Science episodes, especially when one of us is going to be gone. Dylan has an unplanned absence right now. He's actually supposed to be here. We are going to do two sessions on this book and I am not going to be on the second one. So that's the main reason we had Chris on. But we are very. So. So we. We just loaded you up with this at the last. More or less at the last minute.

1:30 Christopher: It was actually the reading. The book's actually pretty breezy. I mean, even says he wrote it for a less technical audience initially.

1:36 Mark: Right. He wrote a book called Scientific Essentialism 2001. And this is, I guess, supposedly the popular version of this. It does not read to me like a popularization.

1:46 Christopher: Popular is definitely not the right word.

1:48 Mark: Wes. Opening should give you a clue on the kind of terminology that he likes to use. He's pretty precise about it. Yeah. So, Wes, you brought this whole thing up. Give us your intro. What is interesting about this? Why did you pick it?

2:02 Wes: Well, I've been thinking a lot about the subject of gender. Actually, strangely enough, that led to this. And I had a friend who's always challenging me on the subject send me a video, some YouTube video by this German philosopher who said a lot of things that really annoyed me. And one of the things that annoyed me was just this kind of hand waving about the concept of essence that is very typical in certain areas of philosophy. Essentialism is the boogeyman, basically. Yeah. I've been very gradually reading about essentialism and natural kinds and species and various different.

I've been trying to get my Head around all of this stuff because I've never felt like I fully understood it. And then we did Aristotle, which just coincidentally kind of lined up with, I think Mark had been interested in doing that for a while. And that coincidentally lined up with everything I'd been interested in. And this book by Ellis was one of the things that I had been skimming, glancing at, and I thought was particularly useful because it makes a contemporary case for essentialism and it relates it specifically to natural science. I guess I went into it thinking, I wonder, do people, for many people, essentialism is a bad word.

But are there people who call themselves essentialists anymore? They're people who champion essentialism. And I found, oh yeah, okay, this is a whole thing.

3:25 Mark: Although strangely, as we'll get into Ellis, at least in the chapters we read, is an essentialist about chemistry, is essentialist about fundamental physical things. You know, atoms are real, the natural, the elements are natural kinds, because you can very precisely define what is helium, what is hydrogen, by very precise things. And you can say, you know, very precise things about the dispositions that these elements or the compounds of them are going to have. But when you get up to the level of biology, things get much more complicated. And he doesn't have a lot to say about that. You know, it seems like those are not the natural kinds he's concerned with. So I, at least in what we read, if maybe you got into this about gender, but there is nothing that's at all relevant that I saw to that issue.

4:13 Wes: Well, it's indirectly relevant for Aristotle. Interestingly, we've thought of animals, particular animals, as paradigmatic examples of substances with essences, and their species were natural kinds. Aristotle never suggested sex was a natural kind. And he couldn't have, because natural kinds very specifically have to be able to replicate themselves. Right? So it's not like females are producing females and males are producing males. So sex in a way has to be broader or narrow, narrow, however you want to look at it, than natural kind. But all of this is relevant to saying what things are mind independently.

So if I want to say my classifications of the world are non conventional, that they pick out real things in the world, or a matter of my particular interests and cognitive capacities, then it doesn't matter. If rabbits are not a natural kind, they can be well grounded classifications. Something has to be a natural kind. So what Ellis will say is a rabbit is a natural kind cluster. And that if we really want to point to natural kinds, we'd have to have entities that are completely genetically identical, which probably no Two animals are. So we are all species of one.

We are all natural kinds of one, essentially. So this interests me. When I want to talk about what's natural about some human quality like gender or what's not natural. I think you have to think about natural kinds and essentialism. Even if you're not having a debate about whether gender is itself a natural

5:42 Christopher: kind or essential, which could be different.

5:45 Wes: Right. Or involves essential qualities, you could have

5:47 Christopher: natural kind realism without necessarily believing in essentialism.

5:51 Wes: We'll say what you mean by that.

5:52 Christopher: I guess that gets to one of the points I was talking about earlier a little bit where I was just saying that some of it felt a little slippery to me sometimes or I was confused a little bit about what was at stake because it felt like the claim was given by also something like essentialism is going to say there are intrinsically causal powers. Intrinsic causal powers. And then there are natural kinds. And then the third thing is that there are essences.

6:15 Seth: I don't think so, but go ahead.

6:17 Christopher: It felt like to me like they were saying a third thing that there are essences. I guess I would articulate it like this. It's not that H2O is a necessary property of water, it's that H2O is a necessary property of all possible water.

6:32 Wes: Right?

6:32 Mark: It defines what water is. So it is an essential property. It is the essence of water. It is the definition of water. If you change that as opposed to accidental non essential properties where the location of a particular water molecule or how water could be mixed with other things. Is this pure water? I'm not exactly sure when we get into like deuterium or something like that. H3O, I guess that's heavy water. So that's not actually water. You know, you've changed an essential property about it, even if it's has a lot of the same macro properties.

And so this is supposed to ground he had in our Kripke episode long ago. He mentions Putnam. If you went to some other planet and they had something that was functionally the same as water, there's an ambiguity. Pre scientifically, are we referring to a functional characteristic? In other words, whatever it is that we drink and that tastes a certain way and that we wash our hands with or that might be what we're referring to in the first place. But once we discover that all the stuff that's like that insofar as it is the pure stuff is H2O, then if on some other planet something else served the same functional role but was not H2O, it would not be water.

That was Putnam's argument.

7:39 Wes: That was Kripke's argument.

7:40 Christopher: Well, Putnam's was the twin Earth.

7:42 Mark: Right.

7:42 Christopher: But yeah, they both argue their semantic theories of causal reference sort of point to metaphysical necessity.

7:48 Wes: Right. So rigid designators and Kripke. And this goes back to Locke. Right. We have nominal essences, we have classifications based on our macro level experience of the phenomena. We see regularities in the phenomena and we make our classifications. And so we do that with water. For instance, for Kripke, this is a quote unquote stereotype, a fixing mechanism. And we don't know that water is H2O and we don't know that for most of the history, but we assume that there's some underlying essence that explains the regularity of the phenomena and the phenomena, as Aristotle would say, the things more known to us, we know the entity in a sense, but we don't fully know it.

And we can investigate it scientifically and find out that, ah, its essence actually is H2O and it's an essential property because if it loses that property, then it stops being the thing that it is. You can't mess with the water molecule and add something or subtract something without turning it into some other substance entirely.

8:49 Seth: Right. So I think that's where we have to be careful about the way that we are articulating this. What Ellis is going to get to is something to the effect of the thing that is water is defined by these specific properties that mark it off from other things. And all it is to be water is to be the sort of thing that has those essential properties. He's not making a metaphysical claim about substance because the concept of substance is caught up in a metaphysics of predication. And we can talk about later about the whole notion of inert things to which are ascribed properties and external forces and so forth.

He doesn't want to use the term substance in the Aristotelian sense. So the process of identifying a natural kind ceases to be kind of an a priori exercise about definition and it becomes an empirical, scientific exercise about identifying the properties of the thing and going as deep as you can go to get to a point where you have the finite set of essential properties and there's different kinds of properties, as you mentioned, dispositional properties. And some are causal, some are not, various other sorts of things. But I think we should just be cautious about trying to use substance terminology with respect to the way Ellis is trying to construe this.

10:13 Wes: He believes in real essences and he uses the word substance to refer to, say, water or atoms.

10:21 Seth: I'm just saying don't think of it in the terms of substance that we're used to thinking of it, where we're talking about a thing in which predicates adhere or properties adhere in quite the same way. I think the essentialist position has a more nuanced view than that, but we can pick it up later.

10:36 Wes: Yeah, I mean, I don't even think that's the Aristotelian position ultimately.

10:39 Christopher: But we do think he's saying something metaphysical. Right. That it's metaphysically necessary. That's what essence is going to end up amounting to.

10:45 Mark: Right.

10:45 Christopher: I get what Seth's saying that, like, don't think of. Yeah, traditional substance because he's kind of reacting against the idea that there's brute matter strewn throughout an arena of space and the forces act on them. And we don't want to think of it in that way for sure, because that's what he's arguing against. That kind of Humean.

11:02 Seth: The net net of this whole book is he's going to agree there is such a thing as metaphysical necessity. But his claim is going to be metaphysical necessity comes from the ground up. It's these essential properties or the essential characteristics of natural kinds that actually generate the metaphysical necessity, instead of it being pushed down, top down from some kind of abstract power or unconnected, dislocated power kind of a thing.

11:28 Wes: We're going to have to explain metaphysical necessity. And we can either do that now or we can wait until we get into the meat of the book. But we're throwing around that phrase.

11:39 Mark: Yeah, I think we should get out what the main claim is, what he is opposing. Chris just mentioned the Humean picture, which I always thought that Hume was just a weird sort of skeptical outlier. But Ellis knows more about the history of the philosophy of science than I do. And everything we've done on the philosophy of science so far has been about scientific method. It's been about epistemology. It hasn't actually been about the metaphysics of science and in particular, what is the ontological status of natural laws. So I was reminded of when we read GM Anscombe about ethics, that she said, our whole ethics, when we talk about shoulds and rights and is based in a theological framework, God telling us, this is what you got to do.

And so even though lots of ethicists, you know, don't pay attention to that, they still think in terms of rules that we're supposed to follow and maybe we discover them naturally or Something and she just thought that something more fundamental. Actually we have to get back to Aristotle for a more organic, more fitted to the human condition way of talking about normativity. And so likewise, strangely enough, the divine command theory, Ellis is saying, is sort of the paradigm for how the early scientists like Newton thought about scientific laws.

As if God said force equals mass times acceleration, when every reaction must have an equal and opposite reaction. That sounds very archaic and certainly not Humean Hume was. When we say scientific law, all we're talking is saying there is a regularity. We don't know why it is the job of science is just to note what regularities are. And there is nothing deeper than that. Because he was an extreme skeptic and thought you just couldn't dig any deeper. And actually I just taught Hume this last week to my class. Hume considers something like, why is bread nutritious?

Why do we think that bread will help us but eating stones will not? It's just a matter of people have tried it. It's a techne. But of course, there are food scientists now. They know quite a lot about what it is organically, about bread that makes it ingested by our cells in a way that rocks cannot be. So it seems like, haven't we gone beyond the skepticism of Hume? That's very surface level. Because now we feel like we can dive deep into the things themselves. But Ellis is going to say, no, no, no. We still retain the metaphysics of most scientists, he says, or most philosophers of science retains this idea that there's just brute relations between things and retains an idea that the things that are brute relations are basically like Democritean atoms.

In other words, they're things that are just chunks of stuff. In our first Aristotle metaphysics episode, Aristotle was arguing against the idea that basic metaphysics could just be atoms or just the elements or whatever. They have to have something that have inherent motion in them. So Ellis is arguing against this picture that he ascribes to Hume. That is, there's just these things that are inert and they are somehow moved around by laws from we know not where. It's not that we think that God dictated them, but he might as well have, because people think that in other possible worlds the laws of nature could be different.

Right. As far as the logical necessity in does water have to be H2O? Well, lots of philosophers, he says, think, you know, Kripke being an exception, Putnam being exception, think that in some other possible world water could be something else. And so this is the whole picture that Ellis is arguing against he thinks that, no, actually water is inherently this thing, and therefore it has to react in such and such ways. And this really founds, on a very objective basis, all of fundamental, at least chemistry.

15:33 Wes: Chemistry and physics and then indirectly biology. But the view that he's arguing against, that he's associating with Hume, is called passivism. And he doesn't attribute that view to most modern scientists. He thinks most modern scientists implicitly use the metaphysics of essentialism that he's advocating here. It's just philosophers of science happen to be very influenced by this point of view because it kind of made its way into logical positivism and certain other trends in analytic philosophy, and it shows up in such things as possible world semantics.

16:06 Christopher: Yeah, I was going to say metaphysicians specifically too, philosophers of science, for sure, metaphysicians are very influenced still by this passivism, or have been traditionally.

16:14 Seth: Yeah.

16:14 Wes: So the idea is that you could have a world in which materially, all the little chunks of matter are the same, but they just play by different rules. And that's the view that he's going to reject. Right. So he says essentialism, the laws of nature are immanent in the things that exist in nature, rather than imposed upon them from without. So there are real dispositional causal properties that things have. Right. An electron has certain essential properties involving charge, let's say, and its dispositions to behave in certain ways under certain circumstances.

And if that changes, it's no longer electron. You can't do a thought experiment about a possible world in which there are electrons that have different laws of nature governing them, as if electrons were just little ball bearings, you know, And I have a game where I say, okay, the ball bearings behave this way because these are the rules. And here's a different possible world. The ball bearings behave this way with different rules. He's going to say, no, they are actual causal powers and forces that you could say come from the thing, but in a way constitute the thing.

The thing just is those causal powers and forces. And we speak about it. You know, we see these things metaphorically according to material objects at the macro level, like my ball bearing. But of course, that's just a metaphor. And that's not what things deep down, like electrons are. They're not just little chunks of matter that play by certain rules that we can change at a whim or God can change at a whim. They have these causal dispositional essences that are. Involve dispositions to behave in certain ways under certain circumstances. That is what they are.

Mark you Thought, well, maybe this is a straw man in a sense. Do people really think this way? That's not a question I can answer, but it's worth keeping in mind as we go through this.

17:59 Christopher: Might think it's counterintuitive to think of objects as having, at least back then, inanimate objects as having dispositions almost. And so, like water has a disposition to boil at a certain temperature, rather than it being a universal law that water does this, it follows this rule. You'd say, like water itself has the disposition to boil at a certain temperature, which is different than the fact that it boils at a different temperature.

18:21 Mark: Right.

18:21 Christopher: It has the disposition that I can see people think maybe not necessarily find that on the face intuitive, or like objects have the disposition not to accelerate past the speed of light. Talking about that can, I guess, sound a little funky if they thought of them as inanimate. So they didn't think they had kind of intrinsic activity or motion to them. Just up on the surface of it. Obviously, the history of science and the intellectual history there has kind of changed that whole view. Like what he talks about. It just sort of is an interesting side note.

You know, Thomas Kuhn, the philosopher of science, obviously you guys have covered a little bit. He traces the history of metaphysics, of the different paradigms in science. And he talks about how Aristotle's metaphysics resemble more the relativity of Einstein than Newton as kind of a weird how the ontology sort of goes back and forth depending on your commitments or whatever. And it made me think that when Ellis talks about how the scientific paradigm that we're under today seems to point to a kind of critique of the Humean picture of causally inert events that have no real necessary connections to each other and stuff like that as being just false.

That made a lot of sense to me that we would want to shift our understanding or our metaphysics to like, one of, like, relations and dispositions, to have activity and all these things. I mean, that seems intuitive to us today.

19:33 Mark: So to clarify about Hume, it's not that he said that things don't have necessary connections is that we couldn't know that they have necessary connections because we don't see necessary connections. So I think he's leaving it open.

19:47 Christopher: We don't want to commit ourselves to them having these intrinsic, necessary connections.

19:52 Wes: Yeah, someone like Descartes is more apt. And then Malebranche, who was kind of expanding on that because they are reacting against scholasticism. So these Neo Aristotelian explanations in terms of potentiality, which is related to this idea of disposition. And they thought it was not really explaining anything. Right. You say something is dormitive. Why does it make me sleepy? Oh, it's got a dormitive power. It's got a dormitive property. Well, that's just dumb. That doesn't say anything. And if this picture of mechanism was really revolutionary because you could explain the world in terms of, for Descartes, just extended things or extension and extended structures whose only real property is impenetrability.

And the world is like a big gear work of, you know, a clockwork. And things are just interlocking with each other and pushing each other around. And all of our macro level phenomena can be explained in terms of that very appealing idea of mechanism where there are no, none of these occult properties and dispositions and things like that, Unless you want to quibble about Descartes picture. So obviously the world turns out to be much more complicated than that picture. And the question is, has that passivism that's kind of inherent in the Cartesian picture, did that actually survive in the contemporary philosophy of science?

And I think if you think about, say, a possible world semantics, I think it seems clear that in some ways it has. But for the most part, I think we just have to take Ellis's word on it because he's not engaged in this book explicitly with opponents. Right. We're not hearing about all the other modern philosophers who feel differently and him getting into a dispute directly with them.

21:35 Mark: Well, we should say for sure that if Hume's position was that there are no dispositions, or saying that something having a disposition doesn't add any information, that that's just wrong.

21:44 Seth: Right.

21:45 Mark: Bread is nutritious, other foods are nutritious. Nutritious is a disposition. It's just that when we then go scientifically to explore that disposition, this whole view, not just Hume, but the other people that he's Ellis is criticizing would try to look for that disposition in terms of the fine structural properties of something. So basically still inert shapes, like what is the shape of the cell? What are the properties that it has that makes it hook into our stomach in a way that a rock does not.

22:15 Christopher: Yeah. So the dispositions would be like derivative

22:17 Wes: of like more base.

22:19 Christopher: Yeah.

22:19 Mark: So it all comes down to structure.

22:21 Wes: Yeah. Ellis makes a distinction between what we call dispositions at a macro level. Right. Dispositions we observe in the phenomena and then real dispositional properties. And those are not just empirically observable regularities, but those are supposed to be real properties. And the most fundamental kinds of things in the World, everything rests on top of these dispositional properties, not on static, on top of static matter.

22:45 Mark: So I think you're really clarifying a point that I don't know that we've adequately made of what essentialism is. It doesn't mean that all of the properties that we talk about, all the characteristics that we apply to things, gender for instance, are essential. You could be an essentialist about gender, you could be essentialist about this, that there are at least some dispositions, properties, natural kinds that really are structural features of the world. And just saying that that at some level like to make sense of anything, to do science at all, we have to believe that there are these bedrock things that really exist, that we are not just, you know, when we talk about some of the things in really high level physics, we might just say, I don't know, we're just making up some sort of models to account for the data.

We don't know that these quarks really are there. But he thinks that at the level of the chemical and you know, the high level, the biggest objects in physics, again, I don't. When we get down to the quantum

23:43 Wes: level, I don't even know atoms, molecules, electrons, these are all.

23:47 Mark: These are real things. But that doesn't mean that every. So yeah, he gave the example of fragility, that this seems like it should be a natural kind. But no, there's so many different natural properties that could cause something to be fragile. That fragility is just. We have to be nominalists about most of the things that we actually use to categorize things because they are probably not based in some fundamental, really distinct natural kind. It's a bunch of stuff bunched together, you know, that we identify for some particular purpose. So it really is the case that the social constructionists are right about a lot of stuff. Like we carve up the world according to our uses. But Ellis just wants to emphasize that that's not all there is to it. You can't say everything is socially constructed.

24:38 Wes: I don't think the social construction is right myself. But we shouldn't get into that because there's a lot of. Social construction just means too many different things. So yes, our classifications are not arbitrary. Even when they're not picking out natural kinds. It's important to understand that. And they're not arbitrary because the phenomena are related to natural kinds. So even if I have a fuzzy macro level phenomenon like color, for instance, the color blue is not a natural kind in the scheme because it's too fuzzy at some point between Blue and red and even between blue and purple. Right. And I actually went to the color spectrum and I tried to find these individual cases where is that blue or is that purple?

25:18 Christopher: Right. There's a continuum there, right?

25:20 Wes: Yeah. I can't decide. And so we have to arbitrarily make a decision. But of course, to say that we're arbitrarily making the decision doesn't mean that blue isn't a well founded concept just because it's fuzzy at the edges. Of course it is. Blue is a well founded concept and it's different from red. But the natural kinds in this case correspond to each frequency of light. This is analogous to what I call the gene identical micro species. Each frequency of light is a micro species. And then something like blue is not a natural kind, but it's a natural kind cluster. And a lot of phenomena, including I think social phenomena you can speak about in the same way. But go ahead if you have a quote.

25:56 Christopher: The quote that I guess to create the contrast between what you're talking about, the natural kind clusters and the natural kinds that he's like the chemical elements. He has a quote here where he says the distinctions between the chemical elements, for example, are real and absolute. There's no continuum of elementary chemical variety which we must arbitrarily divide somehow into chemical elements. The distinctions between the elements are there for us to discover and are guaranteed by the limited variety of quantum mechanically possible atomic nuclei. And that's him talking about how the natural kinds that he's most concerned with, the ones that there's no continuum with them.

26:27 Wes: You know, what we learned in Aristotle is if there aren't beings like this, there have to be some beings whose properties are all essential and only essential. If this weren't the case, then there would be no beings because there'd be no real unities. This is the only way to ground a mind independent reality is if there are some beings that are in fact are what they are and are the kind of thing they are independently of cognition. So it's not Socrates sitting on a chair that's not the natural kind. It's human being.

26:57 Mark: Can we talk about color for a minute? Because I think this is such a great example and what he had to say about it was pretty surprising to me. I'm looking at page 40 where he has this whole account that I was thinking like Wes, that yes, okay, of course there is a. The color in our minds says the primary secondary quality distinction is different than the thing in the world that causes color in our minds, right? It's a certain texture, it's a certain structure, it's a certain shape. It is not the qualia of red. We know that those are different.

He's saying it's not even true. And then you were pointing out, Wes, the distinctions between, you know, the fact that they have fuzzy edges, but you would still think for a particular shade of blue, like, well, that is this wavelength of light. But he claims if two things are said to be yellow, then certainly they are believed to affect us similarly, namely by both appearing yellow to us under normal lighting conditions. But we are much less sure there's any common basis for the similarity in the objects themselves. And quite sure that if there's any common basis in the things themselves, it's nothing like the color we perceive.

There might perhaps be certain atomic or molecular structures responsible for yellow color perception, but probably even this is not true. There are transmitted interference, diffracted and subjective colors as well as ordinary reflected ones. The processes that give rise to these colors are known to be very different from one another. So the evidence would appear that color perception is a manner in which we are affected rather than a representation in us of what exists in the objects we're perceiving, etc. Just so the fact that it's not that yellow number five you could say is wavelength blah.

Because if you have yellow number 4a slightly the shorter wavelength, but have it in a different observer condition or so I didn't quite understand, it could be the same perceived color.

28:38 Wes: We're dealing with two different things here. One is color perception of objects where you're dealing with reflected light off of things with certain material constitutions and then in an environment that complicates all of that. Right.

28:50 Christopher: I think, yeah. We're also just assuming ideal conditions for looking.

28:53 Wes: Another is just light that when you refract light through a prism and see the color spectrum, I assume you can line up certain frequencies with what the color perception of a human being is going to be, that their faculties are working properly and that you do that in a standard environment. Right. Where yes, I'm not in a room that's just full of red light.

29:14 Christopher: Right. But that's the key is you need to have the ideal conditions, the human cognitions working correctly. All that stuff is irrelevant when it comes to.

29:21 Wes: Yeah, this is all secondary quality stuff. But the point is that however complex and however environmentally dependent on various other factors, our macro level perceptions are, they are linked critically to a mind independent reality which at some level consists of these natural kinds, specifically natural kind dispositions and processes.

29:42 Mark: I'm just not sure how you would get that out of this example. Just to continue a little. The visually discernible spectral colors each correspond to a not very precisely specifiable range of light frequencies, so that each can be produced by the light of many different wavelengths. But the discernible spectral colors are only a small sample of all the colors we're able to distinguish visually. And no color, whether spectral or otherwise, has a unique or precisely defined frequency and intensity profile. In fact, it is possible to match any observable color in many different ways, choosing different combinations of light of different frequencies and intensities.

So it's just, yeah, okay, there's some connection to physical structure that gives rise to what's in our minds, but it's such a complicated one that if that's the only example that we had, we would never arrive at a conclusion that there is an objective world underlying this.

30:29 Christopher: Just given that information. Yeah, it wouldn't be able to.

30:31 Wes: In general, color works pretty well for us. And we don't walk into a room and you see red and I don't see red or. So there are real regularities there, and they're there for a reason. It's not just because we're arbitrarily choosing to carve up the world in a certain way and that we've been trained to do that by society. Society told me to do it.

30:51 Seth: I'm pleasantly surprised by the book. I don't know that we need to go through it line by line because the argument isn't super complicated. And he's spending a fair amount of time trying to associate this with what he calls scientific realism. There are reasons why he thinks this is a good thing, and it's not simply because he's got a beef with rationalist or Humean metaphysics or something like that. He thinks that building a metaphysics, an essentialist metaphysics, will actually make our science better as well as. As you'll see at the end of the book, because I did read through the end, he has the last two chapters talking about philosophical implications and wider implications where he addresses the initial question that Wes raised.

But it'll be interesting for us to talk about all the nuances of dispositional properties and versus, you know, the essential, non dispositional properties and so forth. There's the talk about predication versus properties. So the notion that this is not linguistic, the hierarchy and all that, but really we should, I think, focus on the metaphysical import. Like let's go through and let's get the program down and kind of grant him his assumptions. I think he rightly says in some sense assumed or not fully articulated metaphysics that underwrites our current understanding of science.

32:12 Christopher: That's one of the reasons I said the opening, I said where I was sort of performing a cost benefit analysis on my ontological commitments, because it does seem like that's ultimately what we're going to end up doing, is that what work does this metaphysical theory do for us, which he talks about a lot in the end of the book, because I think that's a lot of his motivation, is that he thinks it does a lot of work for us.

32:29 Wes: I mean, I think maybe start with is it page nine? Then he gives a nice little several bullet point overview. He's in Aristotelian essentialism. This is just before he gets into modern essentialism. Maybe let's start with modern essentialism. Aristotle's conception of essentialism involves essential properties that kind of flow from some internal dynamic in organisms, right? So there are these intrinsic inheritable capacities for development, basically. So the essence of rabbit involves this formal capacity to actually develop into a rabbit. It's passed on from parent to offspring.

So really the focus for Aristotle is species propagation and to some extent functionality. Right. Because he wants to talk about final causes. With modern essentialism, this starts on page 12. It's no longer about biological species because those turn out to be much more complicated. And again, they're natural kind clusters, not natural kinds per se, although they are pretty close to being natural kinds. Just want to say that. But if we really want to define entities that have straightforward essential properties, that if they lose them, they're no longer the thing they are.

We have to look at substances, as in chemical substances, molecules, atoms. So he'll say in the modern essentialism section, we retain the Aristotelian idea of natural kinds, but we reject that with regard to biological species. We move on to atoms and molecules and subatomic particles. Think of species as cluster concepts. We retain this idea about essential properties that he has with the caveat that we make this distinction between individual essences and kind essences. Right? An individual essence. This sort of comes up in Locke is every individual thing has an essence in the sense that it has this underlying structure that if you tinkered with it enough, it would cease to be an entity at all.

You could kill it. You could kill any given entity by depriving it of its essence. But science is specifically concerned with kind essences. It's concerned with not species, as in Aristotle, but it is still concerned with natural Kinds of the sort that we find in chemistry and physics.

34:48 Mark: I think in our Aristotle discussions, we kind of went back and forth between saying that, well, there's a formula for water, H2O, and likewise there's a formula for a particular animal which is its DNA. But of course, the DNA is an individual's DNA. And if we want to determine like which branches of the DNA make it just its individual and which one make it its species. And species are just inherently vague concepts, you know, due to the. This we talked about in our Darwin episode. Just that, you know, what is a neighboring species? Where is the cutoff exactly between an ancestor that is no longer of that type of species? You just can't say in a very sharp way. So even though there is a, you know, an objective, very sharp thing, the DNA there, that would have to be an individual essence rather than a species essence, if we even want to talk that way, which Ellis does not.

35:39 Wes: Aristotle was a bit loose, according to Ellis, about essential properties. In a way, there are these species level essential properties that an individual may lack. So human beings by nature are rational. But I might have gotten a very serious head injury in a car accident, and I'm not that rational. So I can still be a human being and lack one of the supposed essential properties of being a human being. That can't happen with a proton or an atom. Proton cannot lose an essential property and still be a proton. So this kind of the way he's going to talk about natural kinds is. It's much stricter. It's very, very cut and dried and strict. Much stricter than Aristotle. And it, of course only works at this very microstructure level.

36:24 Seth: There's another criteria, not simply that, you know, if you take away an essential property, it's no longer the thing. There's also a sense in which natural kinds are substitutable. They're tokens of a type. So if you have a proton in a particular set of circumstances that exhibits a certain behavior, then if you're going to call something else a proton, then if you put it in that situation, it has to exhibit the exact same kind of behavior.

36:47 Mark: Right. And it's functionally defined.

36:49 Wes: Protons don't have different personalities.

36:51 Christopher: Yeah. It's identical in all essential respects, he calls it. Yeah, yeah.

36:55 Seth: Anything where that substitution would fail. Like you can't take one human being and put it in a different circumstance as another human being and get the exact same behavior. So human being at least is not a natural kind of.

37:08 Mark: The very first sentence of the little summary I wrote for myself, we have not mentioned yet which is natural kinds are not just substances, but processes. So the same thing I was saying that it's not just that dispositions can all be reduced to structural features, it's that it could be that the disposition, the behavior just is basic. So what is a proton? Well, we can say it has this structure, but we can also say it is a thing that has these dispositions that behaves in this way, which when he initially said that, I was like, wait a second, he's a functionalist. So it's not essentially a proton because of its structure, it's because of. Essentially because it does. But I mean, I think that's the point, is the structure and what it does are inextricable.

37:46 Wes: Later on he's going to make this distinction, right, between dispositional and categorical properties. And he's going to claim that the passivists want to reduce all the dispositional properties because they are metaphysically suspect. Right. How does something have a property that it's not manifesting at a given time? It's just this hidden potentiality that seems suspect to a passivist. And so they want to say, well, it's always reducible to some kind of structure that I can imagine and maybe a spatiotemporal structure. And he's going to say, in fact, it's the reverse. Everything in the end has to be reducible for various reasons we can get into to dispositional properties. It's not that dispositional properties are grounded in structural properties, it's the other way around. So I didn't want to just jump us to that. But if you want I can get more specific.

38:34 Christopher: The next thing he talks about in that same section that you were reading from west, the modern essentialism stuff, was he does end up starting to talk about metaphysical necessity, which I know we had touched on a little bit.

38:44 Wes: I thought we should touch on that.

38:45 Christopher: Yeah, I think that that's page 15 or so.

38:48 Mark: Yep.

38:48 Christopher: Yeah, top of 14 and a 15 kind of vibe.

38:51 Wes: So we've all heard of logical necessity, probably mentioned it a million times on the show. Bachelor is an unmarried man. It's true. By virtue of logical form or the connectives of the language. It's analytic necessity. It's a priori, linguistic, formal necessity, whatever you want to call it, logic. Not even God can change it. God can't violate the law of non contradiction any more than you can. And philosophers traditionally distinguish this from say nomological necessity, which is traditionally the kind of necessity you get out of the laws of Nature, physical laws of nature.

And they've made a pretty sharp distinction between those two things, such that you can have things that are true in all possible worlds. And you know, this talk about possible worlds is just a way to formalize our talk about what we can imagine being true hypothetically. So in all possible worlds, we can't violate the rules of logic. Logical truths are true in all possible worlds. But traditionally philosophers have thought, well, we can think of all these different possible worlds with different sorts of laws of nature, even given all the same entities in the world.

And it seems imaginable, and it doesn't seem logically self contradictory, seems conceivable and therefore allowable. And this is something he's going to argue against. So they identify that with metaphysical necessity. And his argument is going to be that metaphysical necessity is in fact stronger and captures nomological necessity, captures the natural law necessity, because dispositional properties are so essentially connected to the things of which they are part that it's not the case that you can think of a world, a different possible world in which there are protons, but protons behave differently.

The powers in things are right there in things.

40:42 Christopher: If something is metaphysically necessary, then it must be the case. And there is no possible state of affairs in which it would not be. Is this quote on 17? To continue, not even God, if there were such a being, could create a world in which anything that is metaphysically necessary is false. If water is H2O, if this is its essential nature, then not even God could create a world in which water is not H2O. To me, he's like collapsing logical possibility and what's metaphysically possible?

41:09 Wes: Nomological. Yeah, he'll say that for essentialists, nothing is logically possible unless it is metaphysically possible. There's nothing that's logically possible that contradicts the laws of nature, because the laws of nature flow essentially from the entities in the world. You can't just set up a world with the same entities and have different behaviors. The entities of the behaviors are too tightly interconnected. Yes, we can imagine it. We can visualize certain things and not others. But that's kind of a trivial, according to him, way of making the distinction, because this idea of what's conceivable, it's simply limited by our cognitive faculties. It's not a good grounds for making this distinction.

41:50 Christopher: And so metaphysical necessities are discoverable only by empirical investigation. And so the same is true of metaphysical possibilities, or what is possible. They're correlative, I guess. He says the concepts of necessity and possibility. Do you have intuitions about this, guys? About whether you can imagine an electron that has a different char, like isn't negatively charged, or do you think it's like, oh, it's no longer an electron?

42:15 Seth: I don't have any intuitions about electrons.

42:18 Christopher: Makes sense.

42:19 Mark: I mean, I think I agree with Ellis on this, but I. I'm thinking sort of the neighboring view that all possibility is merely referring to our lack of knowledge is an epistemic. If we talked about logical necessity before, really we were just talking about, for all we know, it is possible that something could be. But that would cover not just the metaphysically necessary stuff, according to Ellis, but all occurrences in the world. Right. This is the sort of Laplace demon. The entire universe is one tight causal network. Which means that even if I said, well, I could be living in California right now, no, actually, given the state of the universe, so I'm unclear whether this necessity that comes out of the essences of things does then translate to all of the interactions between everything in the universe end up being necessary.

So this seems like it would undermine Ellis's point because Ellis, he still wants to say it's metaphysically necessary that water is H2O. It's not metaphysically necessary that I live in Wisconsin and not California.

43:24 Christopher: Yeah, it's useful to say the natural kinds are going to end up being and their essences are why they're metaphysically necessary. But I don't think he wants to extend it to.

43:31 Seth: Well, you're also talking about two different kinds of statements. I mean, what we're talking about here is laws of nature that are thought to hold universally in all circumstances, in whatever given conditions. And a statement like I could live in California or I live in California is not of that character.

43:51 Christopher: So I kind of find myself agreeing with you, Seth, that I don't have intuitions on whether, you know, are all of the laws of nature or the. As they emerge out of the interactions, are they metaphysically necessary in all possible worlds? It has to be the case that water is always H2O. Or is it possible to think of them as contingent?

44:11 Seth: He drops a lot of examples in the book referencing specific scientific principles or constants that I don't understand, so I don't want to. But let's say there's something like Planck's constant. Let's just keep it really, really simple, that it's not even a law per se. It's just here's a ratio or a measurement that holds between things in whatever the appropriate set of circumstances are. And you say to yourself, well, we could imagine that if the universe was slightly different, that number might be different. Like there is an intuition. I think that's quite reasonable to say, yeah, instead of 5.973, it could be 6.15 or something.

Like you think to yourself, okay, and then what Ellis is asking you to do, and I would suggest that we try it without using reference to possible worlds, just because that already sort of begs the question in some sense, is when you say Planck's constant is a necessary law of nature, what kind of necessity are you talking about? Go back to what Wes just outlined before. Is it definitional, is it logical, or is it ontological? And that's what he's really trying to get at. And ultimately what he says is, we don't really have a strong idea. We know it's not considered ontological because we like to entertain the idea that we could conceive of it differently.

And possible world semantics is just a framework for doing that kind of conception. But ultimately our intuition is, yeah, we can imagine that things would be different. He says, okay, it's not definitional because that's not strong enough. Right. So what kind of necessity are we talking about here? And ultimately, what he's going to say is it's really the type of necessity. If you try to address the necessity question in the. You given the current framework of the empiricist or the, you know, the other historical approaches to metaphysics, you really can't give a satisfactory account of what that necessity is and how it works.

But if you take the essentialist approach, you can. And so maybe we can pick that up in part two, or maybe that's a chapter that I read that we aren't talking about today. I don't know.

46:19 Christopher: But no, I get what you mean. It's one of the claims for why his picture explains more or does more for us is you can now talk about that kind of necessity and being metaphysically necessary and things like that.

46:30 Seth: If you buy his characterization of the traditional worldview, call it rationalist, scientific worldview, that objects are brute matter and laws act upon them, and you say this law is necessary, then you've got a lot of work to do to explain where that law comes from, where its necessity flows from, and how that necessity actually gets acted out in the world on these brute, dumb objects. I mean, I think that's a legitimate critique.

46:59 Wes: We could say something like, there's a possible world in which electrons are not disposed to generate and respond in certain ways. To electromagnetic fields. And you say, well, that's logically possible because I can imagine it. I know it's against the laws of nature of this universe, but maybe the laws of nature are different in that possible world and that hypothetical possible world. This intuition appeals to me because I don't think that makes sense. Because at our bottom layer of ontology, we can't talk about what things are except by talking about their dispositional properties.

It's senseless to say there's such a thing as an electron that doesn't do what it does with electromagnetic fields. That's just what an electron is. And we get ourselves into that frame of thinking because we're doing this very. He'll talk about visualizing a lot, but we're thinking, oh, look, it's the little ball bearing. But it has different rules or different properties that attach to it. It's not a ball bearing. It just is those dispositional properties, so you can't vary them. There is almost something like a logical contradiction in doing that.

48:01 Christopher: Logical necessity, because an electron is just these dispositions. Saying what if an electron didn't have these dispositions Is nonsensical because you're saying, what if an electron.

48:11 Seth: Right.

48:12 Wes: The laws of nature are kind of embedded in things and maybe just are the things. Right. So what we call a thing, again, it's just metaphorical. Like. Like it looks like my. My ball bearing. But at our lowest level of ontology, maybe we just. Just do have these dispositional causal powers or whatever you want to call them.

48:29 Mark: Yep. So that was very surprising to me that I always thought essentialism had to do with objects. Right. Natural kinds of objects. Whereas you're getting us into the fact that they're processes. We're going to have to leave this to the second full discussion, chapter five, that we didn't get to is on laws of nature. But my impression from what we did read was that the whole paradigm of talking about laws of nature, again taking us back to that Anscombe comparison, like laws of ethics, that he just wants to get beyond that talk that. Talking about as you just were, Wes, the properties of things and their dispositions and their behavior toward each other is much more central than talking about.

Of course, it seems like it would be still very useful in science to talk about force equals mass times acceleration and talk about things in terms of laws. So I don't know if he wants to get rid of law talk altogether, but he certainly wants us to recontextualize it.

49:22 Christopher: Laws will emerge out of those relations rather than the laws sort of overbearing the objects or something. Yeah, they'll sort of.

49:28 Wes: Well, he uses phrases like natural laws are the immanent results of natural kinds structure. This is on page 43. But yeah, I mean I think Mark's point is still well taken at a certain point, laws doesn't quite capture what we're talking about, but.

49:42 Mark: All right, thanks for listening. That's the end of part one. Please come back for part two. This very group will discuss this for another hour or so. The these first four chapters. If you are signed up to support us through Apple, you'll see it next week. If you don't support us at all, you'll see it next week. If you're signed up through our website or through Patreon, you can probably get it right now if I posted it promptly as I'm supposed to. See ya.