I have written a few times on my worldview as a whole—my “philosophy of life.” To be viable I believe any worldview must consist of a complete, consilient, coherent, evidence-based account of the six foundations of knowledge: epistemology (which includes semantics), science (which includes history), metaphysics (now more commonly called ontology), ethics (including both morality and metaethics), and aesthetics and politics (both general theory, and particular application). I teach an online course on this every month (among nine others), framed as an introduction to how to be a good philosopher, in a practical and useful way, building your own competent worldview—a skill, and an endeavor, I believe everyone should devote significant time in their life to. All the time the faithful spend on their religions, we should instead spend on this. I wrote up my entire worldview, with an evidence-based defense of it, in 2005 as Sense and Goodness without God: A Defense of Metaphysical Naturalism, and only a little of my views there has changed since. I have also answered questions about my worldview, as framed by others, in How I’d Answer the PhilPapers Survey and How My Philosophy Would Solve the Unsolved Problems and (to a lesser extent) in Eight Philosophical Questions We’ll Never Solve?

But what I haven’t done is explain in a summary and updated fashion why this worldview is almost certainly correct. I believe no worldview comes anywhere near it in internal and evidential coherence and support. Indeed, rarely are other worldviews even constructed into a coherent, consilient, evidence-based whole so as to be tested by these metrics. Most philosophers I have found just have a vague, ill-thought “notion” of what their worldview is, most of it shallow and poorly investigated or tested, even against external evidence, much less any internal logic. This is a particular disease of academic philosophy—the abandonment of systematic thinking for its alternative obsession with micro-problems—as others have noted before, especially Mario Bunge, who lists these as two of seven crippling defects of modern philosophy in his vital yet embarrassingly-ignored work Philosophy in Crisis.

I discuss Bunge’s list, in a context of a wider critique (but also defense) of philosophy as a field of knowledge, in my talk Is Philosophy Stupid? Which you could say represents my “metaphilosophy,” my “philosophy of philosophy.” As such you’ll notice its characteristic dependence on empiricism (I do not reason from the armchair but check the pertinent empirical facts when answering a question like “What is philosophy?” or even “What should it be?”) and consilience (multiple lines of inquiry should converge on the same conclusion; all aspects should be coherent and mutually reinforcing; and the most popular opposing positions among experts on any issue should unify into a synthesis more accurate and complete than any one of them alone, and indeed should inherently explain and thus account for all those disagreements). Which leads me now to recognize a good philosophy should depend on three fundamental heuristics: the truth in any dispute in philosophy frequently (if not in fact always) lies in (1) a protoscientific but empirically testable model that is (2) an explanatory unification (a synthesis) of the leading opposing positions that (3) survives all robust efforts to falsify it.

Why “Naturalism”?

I have already formally defined Naturalism as the set of all worldviews that lack any supernatural ontology: see “On Defining Naturalism as a Worldview,” Free Inquiry 30.3 (April/May 2010), pp. 50-51; and of course my book Sense and Goodness without God III.2 (pp. 67-70). My definition has received recognition in the peer reviewed literature, e.g. Yonatan Fishman, “Can Science Test Supernatural Worldviews?” Science, Worldviews and Education (Springer 2009) pp 165-189. For a thorough discussion of the key terminological distinction here—the natural vs. supernatural in the context of ontology—see my article Defining the Supernatural and my follow-ups touching on various aspects (The Argument from Specified Complexity against Supernaturalism, Defining the Supernatural vs. Logical Positivism, and Naturalism Is Not an Axiom of the Sciences but a Conclusion of Them). In short, all worldviews are either naturalist or supernaturalist; supernaturalist worldviews posit at least one supernatural entity exists, while naturalist worldviews posit none do; and a supernatural entity is anything that is not causally reducible to nonmental objects. Here a mental object is anything distinctively a property of a mind (emotions, thoughts, knowledge, intentions), while a nonmental object is anything that can exist apart from any mind (space-time, matter-energy). In other words, naturalism is any worldview that posits all mental objects causally reduce to nonmental objects, without remainder. Everything is in some respect just a collection of stuff, operating mechanistically (whether deterministically or not, it doesn’t matter), such that “emotions, thoughts, knowledge, intentions” are all the emergent outcomes of interacting systems of mere things, and not irreducible causal properties. Thus we can distinguish supernaturalist worldviews from naturalist ones, and nothing remains.

One can of course be a worldview agnostic, uncertain which worldview is true (meaning, uncertain which is the more probable); but I don’t believe that’s an epistemically sound position to hold for anyone who takes the time to genuinely investigate the matter. One might not have the time or lack interest or for whatever reason not have completed an inquiry; but once one properly investigates and tests the competing alternatives, no genuinely rational evidence-based method will lead you to this kind of worldview agnosticism—nor will it lead you to any kind of supernaturalism.

My old blog carries four articles that still hold up as essential and fundamental reading in my philosophy, and they all converge on the same conclusion that some form of metaphysical (as in, ontological) naturalism is the only remaining credible worldview that even explains how we know things, why we find beauty or value in things, and what all things (like “abstract objects”) even are:

• How to Be a Philosopher
• Epistemological End Game
• Moral Ontology
• Defining the Supernatural

Essential articles establishing this point on my current blog reinforce the point:

• In the matter of epistemology: (1) Advice on Probabilistic Reasoning, (2) Bayesian Statistics vs. Bayesian Epistemology, (3) On Evaluating Arguments from Consensus, (4) A Vital Primer on Media Literacy.
• In the matter of metaphysics: (1) Naturalism Is Not an Axiom of the Sciences but a Conclusion of Them, (2) The Mind Is a Process Not an Object, (3) The Argument from Specified Complexity against Supernaturalism, (4) All Godless Universes Are Mathematical, (5) Six Arguments That a Multiverse Is More Probable Than a God, (6) The Problem with Nothing, (7) Why Life Must Be Complex, and (8) Bayesian Counter-Apologetics.
• In the matter of ethics: (1) The Real Basis of a Moral World, (2) Your Own Moral Reasoning: Some Things to Consider, and (3) My Debate with Ray Comfort.

I have various articles here touching on other aspects of this picture too (e.g. in aesthetics and politics and science), but fundamental theory on those subjects is still to be found principally in my book. Apart from just my blog, I also keep a collection of my essential readings on naturalism in my Writings on Naturalism.

Why “Neo-Aristotelian”

For want of anything better to call it I have sometimes referred to my worldview as Carrier Naturalism, and like terms. But I would rather establish it on a broader basis: the truth should not depend on any particular person’s current understanding, and that includes my own understanding; so calling it “Carrier Naturalism” is misleading and anachronistic. Even my own construction changes from time to time, and others may improve on it substantially beyond; so it should in neither case be designated as simply “Carrier” Naturalism. I have found of late that what I more commonly associate it with is a newly reconstructed Aristotelian worldview. It would be as much folly to call it “Aristotelian” though for all the same reasons; indeed, we have already disproved many particulars of his construction, and built far beyond what remains of it, so calling it such would likewise be misleading. Thus, I am trying out the handle “Neo-Aristotelian,” meaning a modernized, reformed version of Aristotle; in effect, what Aristotle likely would be saying if he had access to all the scientific, historical, and analytical knowledge we have acquired since. We already have some models of how that could go, as ancient Aristotelianism advanced considerably with every generation of new knowledge and findings. For example, my worldview is closer to what we know of Strato of Lampsacus’s reconstruction of Aristotle’s worldview, the third successor to his chair of the Lyceum at Athens, which benefited in advances in knowledge and science made since Aristotle’s day, as I document in Chapter 3 of my book The Scientist in the Early Roman Empire.

Most Neo-Aristotelianism today (like much of what Ross Inman is talking about) is crank theistic claptrap. Like Medieval Aristotelianism, it gets practically everything wrong about what Aristotle even thought or taught. What I am advocating is an authentic Neo-Aristotelianism, one that does not derive from the Middle Ages, but from a careful, unfiltered reading of Aristotle himself, and actually allows recent facts to correct and improve on his fundamental insights; the kind of perspective on Aristotle that would have been immediately obvious to his successors like Strato, and thus not corrupted by Medieval Christian quackery. As such I’m more in line with the science-based Neo-Aristotelians in moral philosophy. The best way to define real Aristotelianism is to do so in contradistinction to the most prominent worldviews competing with it when it emerged: Stoicism, Epicureanism, Platonism, and Pyrrhonism. Aristotelianism shared most in common with Stoicism; and gradually absorbed many of the insights of the atomist Epicureans; and was almost the diametric opposite of Platonism, while being more epistemically optimistic than the typical Pyrrhonist. By the Roman era, eclecticism dominated, and the best scientists (like Hero, Galen, Ptolemy) merged these worldviews into a common, superior, scientific one.

But even that eclecticism was, at its core, Aristotelian:

• It was fundamentally empirical. Aristotle argued for the supremacy and necessity of acquiring observational and experimental evidence for one’s views, and only allowed filling gaps with inferences when observational and experimental evidence was inaccessible. And he emphasized that we should expect any conclusions in the latter category can be overthrown by advances in the former category and therefore we must pursue and encourage continued inquiry. Ironically, the “myth” of Aristotle today as an unempirical armchair thinker is a product of Medieval Christian revisionist history. The truth I document and lay out in my section on the importance of Aristotle to modern science in The Scientist (pp. 99-106; cf. 39-44, and index, “Aristotle”).
• It was primarily reductively physicalist. Aristotle explained all properties and categories as the causal consequence of the arrangement of physical structures (hence, hylomorphism). His delineation of causes as “material” (what something is made of), “efficient” (what something does or is doing), “formal” (the physical pattern or structure of a thing; its overall, quite literal, “shape” or “form”), and “final” (the purpose or goal of an agent’s action) were not meant to be irreducible but mutually explaining: final causes are explained by efficient causes (the correctly arranged mind causes goals and purposes to arise), efficient causes are explained by formal causes (e.g. to Aristotle, the “mind” was the physical pattern of arrangement of material in one’s body; and thus one’s “form” in the sense of a literal, albeit convoluted, “shape”—we now recognize this in the synaptic arrangement of a brain—produced one’s memories and thoughts), and formal causes reduce to simply the arrangements of material causes (objects and things, materials and substances). Aristotle hedged at some points on the outer extremes of his speculation, where it is sometimes unclear where he landed, but we can generate a coherent Aristotelian position, as Strato did, that contained nothing of the supernatural. Was Aristotle’s “Prime Mover” ever separate from the material of the universe and its arrangement? — a consistent Aristotelian would have said no, and Strato eventually did. Were Aristotle’s “fundamental elements” necessarily irreducible powers or could they be the emergent effects of a more fundamental arrangement of simpler subatomic particles? — a consistent Aristotelian would have said the latter, as some later appear to have done.
• It was innovatively formalist regarding abstract objects. This held all the way from numbers to high level abstractions like “love.” Abstractions simply referenced repeating physical patterns in things. Nothing actually exists but when shaped into a material, allowing the physical form to effect all geometrically inevitable efficient causes; and everything else only potentially exists, as a merely possible rearrangement of a material, and thus requires no further explanation than that (in direct contradistinction to Plato). This is one of the most brilliant insights of Aristotle that allowed his worldview to be integrated coherently with physicalist atomism by later eclectic thinkers: everything’s just rearranged stuff in spacetime, all the way down. Aristotle thus took into account the importance of pattern and shape of arrangement, rather than only focusing on the substance of a thing alone. And with this he and his successors could account for all the furniture of reality, abstract and particular.
• It was essentially humanist with respect to axiology (ethics, aesthetics, politics). Aristotle explained morality as the natural causal effect of the human form and its resulting tendencies and needs, and politics as an extension of the need for humans to live morally together in complex societies with limited resources and vulnerabilities. He described morality, like politics, as a technology we invent to serve our needs; above all, our life-satisfaction. Any morality or politics that did not advance human happiness was therefore dysfunctional. And this meant morality and politics had to be empirical sciences, not dictates from heaven nor deductions from ideological presuppositions. Aristotle established the necessity of evidence-based policy, as well as a morality based on actual human psychology, and a theory of aesthetics that was likewise empirical and scientific, reducing everything to the nature of humans and their needs and interests.

Overall, Aristotelianism embraced the three necessary scientific values: the supremacy of empiricism over “authorities” or “armchair” thinking; a belief in scientific and societal progress through continued empirical inquiry; and the valorization of curiosity. And its ethics and politics and aesthetics all prioritized human wellbeing. Within these umbrellas of insight, Aristotle got a lot of particulars wrong, typically because he lacked access to the requisite evidence. But most of his errors were even corrected within two hundred years by subsequent Aristotelian scientists; and they were corrected by applying Aristotle’s own fundamental premises (everything I just summarized above). Thus Aristotelianism was so well-designed at its core that it contained fully adequate mechanisms for its own correction and improvement. And these fundamentals have since been fully vindicated by modern science, in exactly the ways Aristotle would have found quite pleasing.

Consequently, a proper Neo-Aristotelianism today will be empiricist, humanist, and physicalist, and it will achieve a fully coherent explanation of all the observed contents of reality by folding all seemingly non-physical entities, like abstractions and categories and mathematics and natural laws, into physicalism through Aristotle’s insight regarding the roll of form (physical shape) in manifesting causal properties and thus commonalities and differences. For example, morality must derive from human psychology which must derive from neurophysics which must derive, we now know, from evolution by natural selection; and it must attend to, and thus ultimately be based on an assessment of, the actual effects of different attitudes, adopted values, and behaviors. Skipping or denying any of these steps today would be fundamentally anti-Aristotelian. Likewise, cognitive “qualia” (on which see Victor Caston in “Aristotle on Consciousness” in the October 2002 issue of Mind) probably reduces to the unavoidable outcome of physical processes of particular physical structures (see The Mind Is a Process Not an Object). And for what I mean here, see my article Thomism: The Bogus Science, where I cover many examples of Christians claiming to be Neo-Aristotelians in fact prescribing, to the contrary, quite an anti-Aristotelian worldview. By contrast, my book and all my work, especially the articles I referenced above, look far more akin to how Aristotle actually reasoned, and carry forward the actual program he initiated and called for. They produce what would result if we combined Aristotle’s fundamental ideas and trends of thought with all modern scientific (including historical and methodological) knowledge.

Which is why we can be confident a Neo-Aristotelian Naturalism is the most probably true worldview. It is complete, coherent, convergent, consilient, and built entirely on the well-established facts of the sciences. Many things Aristotle foresaw (like that the “soul,” as in the “mind,” would turn out to be a causally-efficacious, patterned arrangement of stuff in the body), have turned out to be true. And everything he got wrong (which has since been corrected) has turned out to also align with predictions his system would have led him to had he more information (like that there had to be a thinking machine, an organ, in the body; he mistook it as the heart—the Aristotelian Herophilus would prove soon after it was the brain).

Two examples will illustrate the point. Aristotle’s theoretical framework and applied empiricism allowed him to anticipate DNA: fetuses and organs must grow and operate following physical mechanistic instructions from some automatic machine within our bodies imparted by our parents, too small to see, but functioning like a computer. He did not yet know about cells or biochemistry or genetics, and thus some of what he imagined about mating and heritability missed the mark; but his analogy ended up being, fundamentally, correct. We just needed to flesh out the particulars. And Aristotle would fully agree with how we did that. Likewise, Aristotle gets much flak today for getting the theory of gravity wrong (Aristotle was a biologist, though, so that some of his hypotheses in physics didn’t pan out should be no surprise: see Ancient Theories of Gravity: What Was Lost? and Galileo’s Goofs: Lessons We Can Learn from Failure), but his fundamental premises remained correct. Aristotle’s core principles led him to conclude gravity had to be a natural (nonmental) property that manifested in a mathematical law of behavior by some efficient cause (we now know it’s the interaction between a gravitational field and a mass), which would reduce to some formal and material cause (which we now suspect is gravitons, which may well simply be twisted-up bits of spacetime: see my article Superstring Theory as Metaphysical Atheism).

It is thus telling that Aristotle’s worst mistakes (such as regarding a Prime Mover) arose when he abandoned his own fundamental principles (such as, in that case most particularly, his hylomorphism and empiricism), a fact not lost on some of his successors (like Strato, who correctly abandoned Aristotle’s theology, and Xenarchus, who correctly abandoned Aristotle’s cosmology).

Consilience and Unification

When you can unify competing theories in philosophy and get a result that not only explains the disagreement but also corresponds to scientific facts and all the core principles above, that’s a good sign you are onto something. For a top illustration of what I mean, see my Open Letter to Academic Philosophy: All Your Moral Theories Are the Same. For another example, see The Gettier Problem. My epistemology in Sense and Goodness without God (now enhanced by Bayesian Epistemology) likewise exhibits what you get when you find a synthesis of the revised positivism of A.J. Ayer, the cognitive intuitionism of Michael Polanyi, and the neopragmatism of the late 20th century (from the neurophilosophical form advocated by Patricia and Paul Churchland then, now to the latest abstract defense by Susan Haack). Each correctly grasped a piece of the problem; there is only one coherent unification of them; and it outperforms them all. This is how philosophy should proceed in every domain; and what it can’t incorporate, it should explain (e.g., any science-based philosophy will discover that the entire philosophy of religion is an error theory; as I’ve since argued under peer-review). I have similarly sought to find where the coherent common ground lies between the fundamental political philosophies of liberals and conservatives, through evidence-based (rather than ideology-based) reasoning tested against the most reliably ascertained facts (it turns out, the liberals are right about most of it; but the conservatives do have a few things to contribute: e.g. see Sic Semper Regulationes and A Strong Rationale for UBI and my section on basic political theory in Sense and Goodness without God, noting that my applied politics has since evolved).

And above all, all six subfields of philosophy should cohere and explain and inform each other. They should not be isolated islands from each other. One’s epistemology is more likely to be correct when it is fully informed by and fully coheres with one’s metaphysics, aesthetics, ethics, and politics, and all the findings of science and history—and in every respect vice versa.

Of course “epistemology” epistemically precedes everything, because you can only know what’s true in every other branch if you are using a reliable epistemology. But your epistemology will become more reliable the more it is informed by the findings of science and history (such as about how the human brain and human societies succeed and fail at epistemic tasks), metaphysics (which, when well-founded on the sciences, will tell you psychic powers and divine inspiration and subjective intuition cannot likely be epistemically reliable, while informing you as to which methods and principles are likely to be), and every other field. Politics and ethics affect which methods we can deem worthy even to employ, e.g. why certain kinds of human experimentation are not acceptable, why manipulating society with a “regime of lies” is a bad idea, how to conduct inquiry and persuasion ethically, and so on. Even aesthetics will tie into your epistemology: a robust epistemology should readily operate successfully in the domain of aesthetics, a useful test of its general value; conversely, we should be able to ascertain what role beauty and ugliness do or don’t play in determining epistemic value (e.g. are “beautiful” explanations more likely to be true—and if so, why?), which requires having a firm grasp on just what beauty and ugliness even are. Which ties us back to metaphysics, which seats us firmly back onto the necessary foundations of science and history. And round and round it goes. Every branch is interconnected with every other; each one informs them all, and each one is informed by them all. And thus they cannot be developed in isolation.

Conclusions follow. For example, where one lands on theism and the supernatural matters to literally everything. Because only nature exists, and hasn’t been planned by any smart, caring God, we need to be very cautious and skeptical and make sure we are right and not being misled by our senses or emotions or patterns of thinking. We need to take seriously a science of knowledge. That’s why naturalists place primary importance on well-tested empirical methods and carefully reasoned arguments, and accounting for cognitive biases and fallacies of thought and other common causes of cognitive and epistemic error. That means the scientific method, empiricism, critical thinking, reason and logic all must take precedence over tradition, intuition (unvetted “gut feelings”), or emotion (of the “if it feels right it must be true” variety), or of course “faith” or “revelation” and the like. And that has consequences for the answers we will find to all the other pieces of the interconnected wheel of philosophical knowledge.

Likewise, since science has only discovered natural facts and never any single supernatural fact, we ought to fill the gaps that remain by following the precedent of how all past gaps have been filled: probably with natural facts and nothing else; because that assumption has worked (and all others have failed) every single time, millions of times now. There can therefore be no rational basis for ever betting against it. Whatever those natural facts will turn out to be, we can hypothesize what they will probably be like based on the most relevant findings of the sciences; because we know whatever fills a gap will probably considerably integrate with them and follow from them, and rarely contradict them. As they always have done to date. So once we’ve absorbed everything science and history can tell us so far, we must limit what else we believe to what is consistent with all those scientific and historical facts. We don’t add what doesn’t have at least some support from the sciences, and we only add what has the strongest support from the sciences (including the well-established findings of history). That means the supernatural doesn’t fill any blanks for us, because science has never found the supernatural filling any blanks before, so there is no epistemic basis for ever expecting it to.

And that in turn has consequences for how one understands aesthetics. Because everything is an unplanned consequence of natural processes, beauty and ugliness are partly what we all evolved to appreciate and avoid, and partly what we each have learned through our childhood and adult life—from our embedded cultures as well as our own unique experiences—to appreciate and avoid. So how we understand what is beautiful and why, can only come from a scientific study of the human beauty response, with any further gap-filling inferences built on that bedrock. Which will in turn affect the weight we attach to what we think is beautiful or ugly, since if it’s partly individualized, we know we can’t expect everyone to share exactly the same opinions we do about what’s beautiful or ugly, nor should they. And if it’s partly universal, but not intelligently designed, then we can’t place too much weight even on our universal ideals of beauty, since they won’t be tied to any cosmic moral truth either. They may be informative, but generally the insight you will end up with is that what you find attractive or distasteful is not automatically therefore moral or immoral. Which in turn will inform what you ought to do about art and aesthetic standards politically. For example, this means there can be no universal standard to employ in restricting speech and art, yet it’s also a scientific fact that trees and certain forms of music and various kinds of urban beautification can all impact crime rate and economic productivity, results surely of interest to everyone’s political aims. And why that is, begs scientific and metaphysical explanation.

It’s all interconnected.

In other words, how we decide what is beautiful or ugly will certainly be affected by why things are beautiful and ugly, which we will only know from science and metaphysics, and what we conclude is beautiful or ugly and why might affect what we regard as moral or immoral or legal or illegal or politically important or unimportant and what we should or shouldn’t create or fill our lives with. And this same circle of interconnections affects every other domain, from science itself to metaphysics and ethics and politics and, again, epistemology. A correct worldview by definition must exhibit such interlocking coherence and mutual explanation, with some complete explanatory reduction, and do so without ignoring or contradicting the trends of all human sciences. So the fact that Neo-Aristotelian Naturalism does this, and so well, is a well and good sign it’s on to something. And if you aren’t sure, just pick at any thread within it and try your damnedest to falsify it—not arbitrarily deny or doubt it, but actually disprove it. When you’ve done this with enough threads and never succeeded, despite serious trying, the odds are, you’ve lit upon the truth—or something near enough on present information. And future information, you can reliably bet, will only further confirm this is generally true, even when it revises the particulars, as we can expect it will.