Sufficient Reason for Brutality
A chat about the principle of sufficient reason and modality
For a breezy introduction, listen to a generated Deep Dive podcast here.
July 2, 2023
Prompt:
By the lights contemporary philosophy, when was the principle of sufficient reason put to rest?
ChatGPT:
The Principle of Sufficient Reason (PSR) has not been universally "put to rest" in philosophical circles, even though its universal application has been heavily critiqued in light of quantum mechanics and certain metaphysical arguments.
In the early 20th century, quantum mechanics introduced a level of fundamental indeterminacy that seemed to contradict the PSR. Many interpretations of quantum mechanics suggest that certain events, like the decay of a radioactive atom, have no sufficient reason—they just happen.
Furthermore, philosophers like David Hume and Immanuel Kant critiqued the principle. Hume argued against the necessity of cause and effect, while Kant claimed that applying the PSR beyond the realm of possible experience (i.e., to explain the existence of the universe itself) would lead to antinomies, or self-contradictions.
Despite these criticisms, many philosophers still find the PSR useful in various forms, and it continues to play a role in discussions about modality, causation, explanation, and metaphysics. The PSR is still very much alive in contemporary philosophy, even if its universal application is often considered untenable.
Prompt:
Has it received a critical treatment from any analytic philosophers of metaphysics not otherwise interested in the philosophy of religion or non-classical logic?
ChatGPT:
While discussions of the Principle of Sufficient Reason (PSR) are often linked to philosophy of religion and non-classical logic, it is also a topic of interest in more general metaphysical debates. However, direct engagement with the PSR by analytic metaphysicians who aren't otherwise invested in philosophy of religion or non-classical logic can be more rare, as the PSR isn't as central to some of the more mainstream topics in contemporary metaphysics.
It's also important to note that acceptance or rejection of the PSR often takes place implicitly in a philosopher's broader metaphysical system, even if they don't explicitly discuss the PSR. For example, a philosopher who strongly emphasizes the role of causality and explanation in their metaphysics might be seen as implicitly accepting some form of the PSR, while a philosopher who accepts brute facts might be seen as rejecting the PSR.
Unfortunately, it's hard to provide a specific list of such philosophers without more context, since engagement with the PSR can take so many different forms. Still, the general trend in contemporary analytic metaphysics is to be cautious about the PSR, particularly in its stronger forms, due to its potential to rule out indeterminacy and brute facts.
Prompt:
The PSR seems truth-functionally equivalent to whether there are both necessary and contingent truths.
ChatGPT:
The relationship between the Principle of Sufficient Reason (PSR), and the concepts of necessary and contingent truths is indeed an interesting one. Let's break this down.
A necessary truth is a statement that could not have been false, that is, it is true in all possible worlds. For instance, the statement "all bachelors are unmarried" is necessarily true.
A contingent truth, on the other hand, is a statement that is true in our world, but could have been false in another possible world. An example would be "it is raining today". This is true today, in our world, but could be false tomorrow or in another possible world.
The PSR asserts that for every fact F, there must be an explanation why F is the case. Now, the connection to necessity and contingency comes into play when we consider what kind of explanation is required.
If we say that every fact has an explanation, and that this explanation itself needs an explanation, we might eventually end up with a chain of explanations that either goes on indefinitely, or terminates in a necessary truth – something that just has to be the case, without further explanation.
So, in this sense, you could say that the PSR and the concept of necessary truths are related: the PSR might ultimately require that there are necessary truths.
However, it is important to note that the PSR and the existence of necessary truths are not logically equivalent. The PSR is a principle about explanation, while necessary truths are a type of truth. It is possible to question the PSR while accepting necessary truths, and vice versa.
Similarly, the PSR could be used to argue against the existence of contingent truths, if one interprets the PSR in such a way that it doesn't allow for brute facts – that is, facts that just are the case, without further explanation. However, again, the PSR and the existence of contingent truths aren't logically equivalent, and it's possible to accept one while rejecting the other.
In summary, while there are interesting connections between the PSR and the concepts of necessary and contingent truths, these are distinct concepts and not truth-functionally equivalent. The relationship between them depends on one's specific interpretations of these concepts and one's broader philosophical views.
Prompt:
The connection I have in mind is that if all explanations are finite, then the contingent truths are just the brute facts and those facts ultimately explicable only by deduction from brute facts. Here I assume explanation by deductive inference and the finitude of explanation.
ChatGPT:
I see, that's a very insightful point. If we assume that all explanations are finite and occur through deductive inference, then indeed we would be led to the conclusion that contingent truths are either brute facts themselves or are derived from brute facts.
In this view, a brute fact is a contingent truth that doesn't have a further explanation – it's just true in our world, but could have been false in another possible world. All other contingent truths would then be deducible from these brute facts.
These brute facts would form the foundation of our network of explanations, since they would be the starting point from which other truths are deduced. Given the finitude of explanation, we wouldn't have an infinite regress of explanations – instead, explanations would ultimately terminate in these brute facts.
So, under these assumptions, the Principle of Sufficient Reason (PSR) would need to be modified or rejected, since not all facts would have an explanation. Only necessary truths (which are true in all possible worlds) and truths that can be deduced from brute facts would have explanations. Brute facts themselves would not have explanations – they would just be contingently true.
Again, this shows how the relationship between the PSR, necessary truths, and contingent truths can be quite complex and depends on one's specific assumptions and views about explanation and inference.
Prompt:
What are other commons assumptions, or lack of assumptions, can sever or complicate this connection between the PSR and modality?
ChatGPT:
Indeed, there are several ways in which the connection between the Principle of Sufficient Reason (PSR) and modality (the philosophical study of possibility and necessity) can be severed or complicated. Here are a few:
Non-Deductive Inferences: In your previous scenario, you assumed explanations happen through deductive inferences. However, if we also consider non-deductive inferences, such as inductive or abductive reasoning, the connection between the PSR and modality can become more complex. Non-deductive inferences might not lead to necessary truths and could potentially explain contingent truths without requiring brute facts.
Infinite Explanations: Your scenario assumed explanations are finite, which avoids an infinite regress of explanations. If we reject this assumption and allow for infinite chains of explanations, this could alter the connection between the PSR and modality. It could be possible, for instance, that every contingent truth has an explanation, but that these explanations form an infinite chain, without any grounding in necessary truths or brute facts.
Broadening the Notion of Explanation: The PSR states that every fact has an explanation, but what counts as an "explanation" can be subject to interpretation. If we allow for broader or more diverse kinds of explanations, this could sever the direct link between the PSR and modality. For example, some philosophers argue for "grounding" or "making up" relations as forms of non-causal explanation, which can complicate the picture.
Different Modal Frameworks: The connection between the PSR and modality can also be altered by adopting a different modal framework. For example, in a system of "deontic" logic, which deals with obligation and permission, or "doxastic" logic, which deals with belief, the relationship between explanation and necessity/contingency could look quite different.
These are just a few ways in which the connection between the PSR and modality can be severed or complicated. The relationship between these concepts can be quite complex and depends on many assumptions and philosophical choices.
Prompt:
Even if explanations could go on infinitely, they would never finitely explain, since incompletely articulated.
ChatGPT:
Yes, that's a key insight. If an explanation is part of an infinite chain, then it could never be fully given in a finite amount of time or space. This is sometimes called the problem of "infinite regress." An infinite explanatory chain might not be satisfying, as we wouldn't have a complete explanation at any finite point.
Moreover, this situation would challenge our usual expectations about what it means for something to be explained. Usually, when we seek an explanation, we're looking for something that provides a satisfactory answer to our question within a finite framework. If explanations could go on indefinitely, then it would seem that no explanation could ever fully satisfy our inquiry.
So, while allowing for infinite explanations could technically avoid a violation of the Principle of Sufficient Reason (since every fact would still have an explanation), it might not meet our intuitive expectations for what good explanations should do, namely, provide understanding within a finite framework.
This is why many philosophers prefer to avoid infinite regress, and why they might opt for explanations that terminate in necessary truths or brute facts, as you previously suggested.
Prompt:
If the explanation of a contingent fact were to terminate in a necessary one, then the explanatory steps would have to be other than deductive, since contingent truths are not deducible from necessary ones.
ChatGPT:
You're correct. In deductive reasoning, the truth of the premises guarantees the truth of the conclusion. Therefore, if you start with only necessary truths (which are true in all possible worlds), you cannot deduce a contingent truth (which is not true in all possible worlds) through a purely deductive process. In other words, you can't get contingency from necessity using only deduction.
To get from a necessary truth to a contingent one, you would need some form of non-deductive reasoning, such as inductive or abductive reasoning, or perhaps some form of modal reasoning that incorporates both necessary and contingent elements.
Alternatively, you could have a system where necessary truths and contingent truths are linked through some form of causal or grounding relationship, rather than a purely deductive one. In such a system, a necessary truth could somehow "give rise to" a contingent truth, even though the contingent truth isn't strictly deducible from the necessary one.
This highlights an important aspect of the Principle of Sufficient Reason and its relation to modality: getting from necessary truths to contingent ones can be quite complex, and doing so may require going beyond simple deductive inference.
Prompt:
Inductive or abductive reasoning appears no more suited to the task. From necessary particulars, inductive generalization to a universal will also not yield a contingent truth. The class of propositions explained by any set of necessary truths is the same at every possible world, since the explanation itself isn't contingent.
ChatGPT:
You're absolutely right. If we start with only necessary truths, inductive or abductive reasoning won't be able to yield a contingent truth. This is because, as you rightly noted, the class of propositions that can be explained by a set of necessary truths will be the same in every possible world.
The point you've raised highlights a fundamental issue in the philosophy of explanation and modality: how do we account for the existence of contingent truths? If all explanations must ultimately terminate in necessary truths, as the Principle of Sufficient Reason (PSR) might suggest, then how can we explain the existence of truths that could have been otherwise?
There are a few ways philosophers might try to address this issue. One is by modifying the PSR to allow for "brute facts," which are contingent truths without further explanation. Another is by introducing a causal or grounding relationship between necessary truths and contingent ones, as I mentioned earlier.
However, none of these solutions are entirely without problems, and the question of how to account for contingency remains a central issue in metaphysics. This is part of what makes the PSR, and the philosophy of explanation and modality more generally, such rich and complex areas of study.
Prompt:
Let us explore the causal or grounding relations. How would these account for the explanation of the contingent by the necessary?
ChatGPT:
Causal or grounding relations provide an alternative way of looking at the explanation of contingent facts that sidesteps the issue of deriving contingency from necessity through deductive reasoning. However, these approaches come with their own sets of considerations and challenges.
Causal Relations: In the case of a causal relation, a necessary fact could causally give rise to a contingent fact. For example, consider the laws of nature, which are often treated as necessary truths in certain philosophical interpretations. These laws causally govern the behavior of entities in the universe, which can lead to contingent outcomes due to the specific initial conditions of the universe. However, a causal approach to explaining contingent facts via necessary ones requires a specific understanding of causality that allows for necessary causes to have contingent effects, which is not without controversy. Moreover, it raises further questions about the nature of causality and its relationship with modality.
Grounding Relations: Grounding is a metaphysical notion related to explanation where one fact is said to "ground" another, meaning that the grounded fact depends on the grounding fact. Grounding relations, much like causality, are used to express asymmetrical metaphysical dependence relations. One might propose that necessary truths can ground contingent truths. However, this approach also has its challenges. Grounding is a controversial and complex notion in contemporary metaphysics, and it's unclear under what conditions a necessary truth can ground a contingent one. It would require a robust account of grounding that can accommodate this kind of relationship.
It's important to note that both of these routes require further philosophical commitments and open up new questions. They offer potential ways to account for the existence of contingent truths given the PSR, but neither provides a simple or uncontroversial solution. These are active areas of philosophical research, with ongoing debates about the nature of causality, grounding, and their respective roles in explanation.
Prompt:
Regarding causality, how could a necessary cause have a contingent effect?
ChatGPT:
In a typical understanding of causality, the relationship between cause and effect is such that if the cause occurs, the effect must necessarily follow. However, this becomes complicated when we consider the relationship between necessary causes and contingent effects.
A common approach is to think of necessary laws of nature interacting with contingent initial conditions to produce contingent outcomes. In this view, the necessary laws dictate how things behave under various conditions, and the contingent initial conditions determine which laws are relevant and how they apply.
For instance, consider the law of gravity (assumed here to be a necessary truth). This law doesn't specify that an apple must fall from a tree. Instead, it describes how objects with mass will behave under various conditions. Whether an apple falls from a tree is contingent on a variety of factors - the apple existing, the apple being detached from the tree, etc.
The initial conditions (the state of the apple, the tree, the Earth's gravitational pull at the time) are contingent, and they interact with the necessary law of gravity to produce a contingent outcome - the apple falls from the tree.
However, this view assumes a kind of causal modality where necessary laws can interact with contingent conditions to produce contingent outcomes. This is not without controversy and is a matter of ongoing philosophical debate.
This is a very complex area of philosophy, with deep connections to metaphysics, philosophy of science, and the philosophy of modality, and it's still a subject of active research and debate.
Prompt:
This happens to be my own view of causation and modality. But here again, the necessary truth, or law, does not cause the contingent truth, or effect, alone. It does so in conjunction with the initial conditions, but these conditions are themselves contingent, and the conjunction of necessary and contingent truths is contingent.
ChatGPT:
Absolutely, your observation is spot on. In the interaction between the necessary laws and contingent initial conditions to yield contingent outcomes, both elements play a crucial role. The necessary laws guide how the conditions unfold, but the specific initial conditions — which are themselves contingent — are crucial in determining the particular outcome.
As you correctly pointed out, the conjunction of necessary and contingent truths is itself contingent. This is because the outcome is dependent on the particular initial conditions which could have been otherwise. Thus, while the necessary laws provide a framework for how things could happen, the actual events that do happen are contingent on the specific circumstances.
This view underscores the complex interplay between necessity and contingency in our understanding of causation and explanation. It navigates a path that respects the PSR (by providing an explanation for all events that happen) while still allowing for the existence of contingent truths (by incorporating contingent initial conditions into the explanation).
However, as you've noted, the necessary laws do not alone account for the contingent outcomes. This reinforces that, in some form or another, contingency is a fundamental aspect of our world, whether it appears in the form of contingent initial conditions, brute facts, or in some other manner.
Prompt:
Similarly for grounding, I would say, with the notable difference being the temporal and identity relations between explanandum and explanans.
ChatGPT:
Your insight is correct. Grounding, like causation, is a relation of metaphysical dependence, but it typically doesn't carry the same temporal or identity implications as causation.
Temporal Implications: Causal relations are usually thought of as being temporal in nature, with causes preceding their effects in time. Grounding relations, however, are typically thought of as being atemporal, meaning that they aren't tied to a specific time or sequence of events. For instance, the fact that a square has four sides is grounded in the definition of a square, regardless of when the square exists or the definition is considered.
Identity Implications: Causal relations often preserve identity across time, such that causes and effects are understood as distinct entities or events. Grounding, on the other hand, is often conceived in a way that allows for the grounded and grounding entities to share an identity. For example, one could argue that a person's being a bachelor grounds their being unmarried, and in this case, the person is the same in both facts.
Yet, like in the case of causation, if grounding is to bridge necessary and contingent truths, the conjunction of the grounding necessary truth and any additional contingent truths (which may be required to fully specify the grounded contingent truth) would itself be contingent. Thus, although grounding offers a promising avenue for exploring the relationship between necessity and contingency, it doesn't entirely eliminate the need to account for contingency.
Prompt:
What other considerations remain outstanding in favor of the PSR? I believe we have considered the finitude of explicability, and the impossibility of inferring, even non-deductively, the contingent from the necessary.
What about the broadening of explanation or different modal frameworks? How could these considerations justify explanation of contingency from necessity?
ChatGPT:
Broadening the notion of explanation and considering different modal frameworks indeed offer alternative perspectives on the relationship between necessity and contingency, and how to account for the Principle of Sufficient Reason (PSR).
Broadening Explanation: When we consider explanations, we typically think in terms of causal or deductive explanations. However, the landscape of explanation is arguably much broader. In philosophy, for example, there are teleological explanations (based on goals or ends), statistical explanations, genetic explanations (based on the origin or development of something), and others. If we allow for a wider variety of explanatory types, it might be possible to find a way to explain contingent truths in terms of necessary truths, though these would likely require additional philosophical commitments. For instance, in a teleological framework, contingent truths could be seen as resulting from the inherent goals or ends contained in necessary truths. However, this would require accepting that necessary truths can contain teleological principles, which is a substantial philosophical commitment.
Different Modal Frameworks: The standard modal framework differentiates between necessary truths (those that hold in all possible worlds) and contingent truths (those that hold in some but not all possible worlds). However, there are different modal frameworks that might offer new perspectives on the relationship between necessity and contingency. For example, in a framework of "conditional necessity", a fact could be necessarily true under certain conditions but not others. This could potentially allow for necessary truths to give rise to contingent truths under certain conditions, creating a bridge between necessity and contingency. Alternatively, one might consider a "graded" or "degree-theoretic" approach to modality, where truths can have degrees of necessity or contingency. In such a framework, it might be possible to view contingent truths as "arising" from necessary truths in a gradual or graded manner.
These approaches offer intriguing possibilities, but also come with their own set of challenges and require additional philosophical commitments. For instance, broadening the types of explanations accepted raises questions about the nature and purpose of explanation, and adopting different modal frameworks might require substantial revisions to our intuitive understanding of necessity and contingency. As always in philosophy, the exploration of these options is part of ongoing debate and research.
Prompt:
While I accept that some truths are teleological, I do not accept that any necessary truths are teleological.
ChatGPT:
Your perspective aligns with many in the field of philosophy. Teleology, or explanation by reference to purposes, goals, or ends, often seems to fit comfortably in the realm of contingent truths. For example, the statement "The bird is building a nest to lay eggs" is a teleological explanation, but it's clearly contingent – it depends on specific conditions and wouldn't be true in all possible worlds.
The idea that a necessary truth could be teleological might seem counterintuitive. Necessary truths, by definition, are true in all possible worlds. However, it's not immediately clear how a goal or purpose could be true in all possible worlds, as goals and purposes seem inherently tied to specific circumstances, agents, and contexts, all of which are contingent. For example, the goal of a specific bird to build a nest is dependent on the existence and circumstances of that bird.
That being said, some philosophers have proposed teleological interpretations of certain necessary truths. For instance, in the philosophy of biology, some argue that certain biological principles or laws have a teleological character, as they appear to drive systems towards certain ends or goals. Similarly, in philosophy of mind, certain cognitive or perceptual processes are sometimes interpreted in teleological terms. However, these interpretations are often controversial and subject to ongoing debate.
So, your position is quite reasonable, and indeed aligns with a common intuition about the relationship between necessity and teleology. As with many issues in philosophy, these are complex questions without clear-cut answers, and are subjects of active discussion and research.
Prompt:
I admit that the processes of life and mind are teleological, but would insist that biological and cognitive laws themselves are not teleological. The purposes are etiologically determined, and the relevant origins are contingent.
ChatGPT:
Your perspective fits well with a common understanding in the philosophy of biology and mind. As you've highlighted, teleology seems to be more appropriately linked with biological and cognitive processes rather than with the laws governing these processes.
In this view, the laws themselves are not teleological but describe how systems behave or evolve. The apparent teleology emerges from the processes these laws govern, particularly when these processes are part of complex systems like organisms or minds that have evolved under certain contingent conditions.
For instance, the purpose of a bird building a nest isn't contained in the laws of biology but emerges from the specific biological and environmental circumstances of the bird. The laws provide a framework that allows for such purposeful behavior to arise under certain conditions.
This understanding, which separates the teleological aspects of processes from the non-teleological nature of the laws themselves, is a compelling way to accommodate the apparent teleology we observe in the world within a naturalistic and scientifically-informed framework.
Prompt:
I also accept that modality is graded, and indeed that these grades are generated by the very conditions against which there is relative necessity. But these relative necessities are such that a contingency is entailed by a necessity only if contingency is of a lower grade than that of the necessity, where the lowest grade of necessity is the most fundamental, or least conditionalized.
ChatGPT:
The view you've articulated is an interesting one. In this approach, modality is not binary (necessary vs. contingent) but graded. Things can be more or less necessary or contingent depending on the degree to which they're subject to certain conditions. This provides a richer framework for understanding the nature of modality.
The specific way you've structured this graded modality is also intriguing. You've suggested that a necessary truth can entail a contingent one only if the contingent truth is of a lower "grade" of necessity – that is, it is subject to more conditions or less fundamental than the necessary truth. This provides a sort of hierarchy or structure to modality, where higher-grade necessary truths can give rise to lower-grade contingent truths, but not vice versa.
This perspective allows for a nuanced understanding of the relationship between necessary and contingent truths and provides a potential route for reconciling the Principle of Sufficient Reason (PSR) with the existence of contingent truths. That being said, as with any philosophical view, it comes with its own set of questions and challenges – such as how exactly to define and measure these "grades" of modality, or how to handle truths that might be subject to multiple, potentially conflicting conditions. It's an interesting position that contributes to the ongoing philosophical discussion about the nature of modality and the PSR.
Prompt:
This does not favor friends of the PSR, however, since these conditions are themselves ultimately brute facts.
ChatGPT:
That's a very astute point. Even with a graded model of modality, the very conditions that determine the grades of necessity or contingency are themselves contingent. They are often considered as "brute facts", which exist without further explanation.
In other words, although this graded framework might give us a more nuanced way to understand the relations between necessary and contingent truths, it does not fully satisfy the demands of the PSR because the conditions themselves are left unexplained. They exist as brute facts, and thus some level of contingency seems inescapable.
This highlights a key challenge for proponents of the PSR: how to account for the fact that our world seems to include both explainable phenomena (which fit nicely with the PSR) and brute facts (which don't). The tension between these observations, and how to resolve it, is a central issue in the debate over the PSR and its place in our understanding of the world.
Prompt:
There is another argument that a necessary being or event can cause a contingent event, but I don't see how that would work.
ChatGPT:
The argument that a necessary being or event can cause a contingent event is indeed a point of discussion in the philosophy of religion and metaphysics. However, as you've noted, there are challenges associated with this viewpoint.
Here's how the argument generally goes: proponents suggest that a necessary being or event (God, in the philosophy of religion, or the Big Bang in cosmology, for instance) sets the initial conditions of the universe. These conditions, though determined by a necessary being or event, unfold in various contingent ways depending on a range of factors, giving rise to the contingent events and entities we observe in the world.
However, this brings us back to a point you've rightly raised earlier in our discussion: even if a necessary being or event sets the initial conditions, those conditions are themselves contingent. They could have been different. So while the necessary being or event might cause or give rise to contingent events indirectly by setting initial conditions, it doesn't seem to cause contingent events directly.
This is a deeply complex and much-debated issue with connections to many areas of philosophy. It illustrates the ongoing challenge of understanding how the necessary and the contingent are related, and how best to account for the existence of both types of entities and events in our world. As always in philosophy, these issues continue to be subjects of active exploration and debate.