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Why Do Logic and Mathematics Seem to Transcend Matter?

Why do logical laws and mathematical truths seem universal, necessary, and independent of the physical world—yet describe that world with astonishing precision? This article explores whether numbers and logic are invented, discovered, or grounded in a deeper rational order, and asks which worldview best explains their objectivity, knowability, and remarkable fit with nature.

Why Do Logic and Mathematics Seem to Transcend Matter?

A mathematician writes an equation on a board. The chalk is physical. The board is physical. The movement of the hand is physical, and so are the electrical and chemical processes firing inside the brain. But what about the truth the equation expresses?

The symbols can be erased without making the equation false. Every mathematician who understands it may die without altering its logical consequences. Another civilization could write the same relationship using entirely different marks. The physical inscription is plainly not the same thing as the mathematical truth it communicates.


Logic presents a similar puzzle. We can write the law of noncontradiction on paper, but the law is not made of ink. We can think about it using neurons, yet its validity does not seem to depend on the condition of anyone’s brain. A damaged brain may fail to reason correctly; it does not thereby change what correct reasoning is.

Observations like these have led many philosophers to conclude that logic and mathematics cannot be explained purely as physical objects or events. Others resist that conclusion, arguing that mathematical language can be understood through human conventions, conceptual constructions, formal systems, or useful fictions.

So the question is not settled by simply declaring, “Numbers are immaterial, therefore God exists.” Serious philosophers disagree about whether numbers exist at all, what mathematical statements even refer to, and what kind of reality logical laws possess. The honest version of the question is comparative:

Which account of reality best explains the objectivity, necessity, knowability, and remarkable usefulness of logic and mathematics?

What Does It Mean to “Transcend Matter”?

To say that logic and mathematics seem to transcend matter does not mean they float somewhere above the universe as ghostly objects. It means they have features that are hard to identify with any particular physical thing.

Consider the statement:

Two plus two equals four.

The sentence on a screen is physical. The spoken sounds are physical vibrations. The mental act of considering it presumably involves the brain. Yet the truth of the statement does not appear to sit at any address. It has no weight, temperature, charge, or size. And under the ordinary meanings of the terms, it does not merely happen to be true — it could not have been false.


Physical conditions could have been otherwise. The universe might have held fewer galaxies. Earth might never have formed. No human civilization might ever have arisen. But it is hard to imagine how any of those changes could make two and two stop equaling four. That contrast — between contingent physical facts and seemingly necessary truths — sits at the heart of the problem.

In plain terms:

Contingent means “could have been otherwise” — Earth might never have formed. Necessary means “couldn’t have been otherwise” — two and two can’t make five. The physical world is full of contingent facts. Mathematics looks like it’s full of necessary ones. That mismatch is the whole puzzle in a sentence.

There is an important qualification, though. Not every naturalist believes only physical objects exist. Some naturalistic philosophers accept abstract mathematical entities precisely because mathematics seems indispensable to our best science. So naturalism, physicalism, and nominalism should not be treated as interchangeable. The challenge here bites hardest against a strictly reductive materialism — the view that nothing exists beyond concrete physical reality.


Philosophers call something abstract if it isn’t made of matter, isn’t located in space, and can’t cause anything to happen — the number three itself, for instance, as opposed to three coins you can drop on a table. Keep that word in mind; the rest of the essay turns on whether such things are real.

Where Does the Law of Noncontradiction Live?

The law of noncontradiction is usually stated as the principle that something cannot both have and lack the same property at the same time and in the same respect. Aristotle treated it as the most secure principle underlying meaningful thought. In Book IV of the Metaphysics, he argued that denying it threatens the very possibility of definite meaning and rational discourse.

Suppose someone claims:

The law of noncontradiction is false.

The claim is meaningful only if asserting that it is false excludes asserting that it is true, in the same sense. So the critic seems to lean on a distinction between affirming and denying even while attacking the principle that underwrites that distinction.


This doesn’t mean no philosopher has ever disputed the unrestricted law. Dialetheists hold that at least some contradictions are true, often on the strength of paradoxes such as the liar (“this sentence is false”). Paraconsistent logics have also been built in which a contradiction does not entail every possible conclusion. But paraconsistency and dialetheism are not the same thing: a logician can study a contradiction-tolerant system without believing any real contradiction is true. Dialetheism remains a minority view even among those who work on paraconsistent reasoning.


Still, asking where the law “lives” may already assume too much. A nominalist replies that logical laws aren’t objects that need locations at all; they are rules governing language or inference. A realist says they express necessary features of reality. A conceptualist reads them as structures of rational thought. And a theistic conceptualist grounds them in the eternal divine intellect. The question is not geographical but ontological: what kind of thing, if anything, is a logical law?


In plain terms:

“Ontological” just means “about what exists and what kind of thing it is.” The disagreement isn’t about which shelf to find the law of noncontradiction on. It’s about whether it’s a thing at all, a rule we follow, or a truth that was already in force before anyone stated it.


It is worth noting that some Christian philosophers have pressed this specific point into an argument. James Anderson and Greg Welty, for example, have argued that the laws of logic are best understood as thoughts — and that necessary, universal thoughts require a necessary, universal mind to think them. Whether or not one finds the inference decisive, it shows that the “location” of logical laws is live philosophical territory, not a settled matter.

Are Mathematics and Logic Invented or Discovered?

The familiar debate between invention and discovery can mislead, because mathematics seems to involve both.

Human beings clearly invent the symbols (“2,” “π,” “=”), the terminology and notation, systems of measurement, definitions, particular axiomatic frameworks, and the questions mathematicians choose to pursue. There is nothing inevitable about writing the number after one as “2”; another civilization could use a different mark without practicing different arithmetic.


Yet once definitions and axioms are fixed, their consequences don’t seem to bend to preference. A mathematician cannot decide that a valid proof has become invalid because its conclusion is inconvenient. New relationships turn up that nobody anticipated when the original concepts were introduced.


We invent the game of chess — but once the rules are set, we discover which positions are possible and which strategies win. Mathematics may work similarly, though the analogy doesn’t settle whether mathematical structures are merely rule-governed inventions or realities our systems progressively uncover. A balanced summary is possible: we invent mathematical languages and methods, while discovering relationships that are not under our individual control. What remains disputed is why those relationships carry their apparent objectivity and necessity.


Four Ways of Understanding Mathematical Truth

Philosophers have developed many positions in the philosophy of mathematics. Four matter most for the question of whether mathematics transcends matter. Here they are at a glance before we walk through each:


Platonism

Numbers are real, on their own

Numbers, sets, and functions exist independently of minds and matter. “Three is prime” describes a real object.

Strength: explains why math feels discovered.
Strain: how do physical brains know about causeless, placeless objects?


Nominalism

No abstract objects at all

There is no nonphysical object called “the number two.” Math is symbol-manipulation, useful fiction, or talk we can rephrase.

Strength: lean, tidy ontology.
Strain: then why is a theorem true, and why does math work so well in science?


Conceptualism

Math lives in minds

Numbers are concepts or constructions of rational thought, not a separate realm floating outside every mind.

Strength: no mystery about how we know it.
Strain: human minds are temporary and fallible — did math wait for us?


Theistic conceptualism

Grounded in God’s mind

Math and logic are grounded in the eternal divine intellect — objective, necessary, and knowable at once.

Strength: keeps the best of realism and conceptualism.
Strain: raises hard questions about divine simplicity and aseity.


1 · Platonism: Mathematical Objects Exist Independently

Mathematical Platonism holds, broadly, that mathematical objects — numbers, sets, functions — exist independently of human minds and physical things. The number three is not identical to three apples, three neurons, or the mark “3”; those are physical instances or representations of threeness. The number itself is abstract: nonphysical, nonspatial, and not dependent on anyone’s thoughts. (Modern Platonism should not be confused with accepting every detail of Plato’s own philosophy; it is a family of views united by belief in mind-independent mathematical reality.)


Its strength. Platonism straightforwardly explains why mathematics feels discovered rather than invented. Mathematicians can be wrong because there’s an objective subject matter they can be wrong about. Mathematical truths would hold without human beings, because they don’t depend on us. And Platonism supports reading ordinary mathematical statements at face value: “three is prime” looks like it’s about the number three, not merely a move in a symbol game.


Its difficulty. The great challenge is knowledge. If numbers are causally inert and outside space and time, how do physical human beings know anything about them? We don’t see the number seven through a telescope or detect it in a particle accelerator. Paul Benacerraf’s influential 1973 essay “Mathematical Truth” pressed exactly this: an account that makes mathematical truth objective must also explain how knowers gain reliable access to it. Platonism explains objectivity well but strains on access — and it may leave the astonishing fit between abstract mathematics and physical nature unexplained.

In plain terms — Benacerraf’s problem

We normally learn about the world because things affect us: light hits our eyes, sound hits our ears. But an abstract number can’t touch anything and can’t be touched. So if numbers exist off in their own realm, how does knowledge of them ever reach a brain? That gap — objective truth on one side, no causal bridge to it on the other — is Benacerraf’s challenge.

2 · Nominalism: There Are No Abstract Mathematical Objects

Nominalism denies that abstract mathematical objects exist. Using numerical language, on this view, doesn’t require a nonphysical object called the number two. Different nominalists then explain mathematics differently: some treat it as formal manipulation of symbols; some as a useful fiction — valuable, coherent, wildly effective, without being literally committed to abstract entities; some try to rephrase apparently mathematical claims so they refer only to concrete things and their relations.

Hartry Field’s Science Without Numbers (1980) became the landmark defense. Field argued that mathematics can be useful in science without being literally true of an abstract realm, and — famously — worked out a nominalistic reformulation of Newtonian gravitational theory to show it could be done.


Its strength. Ontological economy: nominalism avoids populating reality with a vast domain of causally inert, nonphysical entities, which appeals to anyone wanting a thoroughly naturalistic picture. It also sidesteps the sharpest form of Benacerraf’s problem — no mysterious contact with numbers is needed if there are no numbers.


Its difficulty. The cost is explaining mathematics’ apparent truth and objectivity. If math is a useful fiction, in what sense is a theorem true? Why can claims be proved rather than just adopted? Why do independent mathematicians converge on the same results? And why is mathematics so deeply woven into successful science? Field’s project shows at least some physics can be rebuilt without numbers, but constructing nominalistic substitutes for the full breadth of modern science is extraordinarily demanding. Nominalism is a serious option, not an evasion — but it must reconstruct much of what realism explains more naturally.

3 · Conceptualism: Mathematics Depends Upon Minds

Conceptualism locates mathematical reality within mental activity rather than in a separate Platonic realm. Numbers and sets are understood as concepts, possible constructions, or structures generated by rational thought — not independent entities existing outside every mind.

It comes in several forms. Some are close to mathematical intuitionism or constructivism; others try to preserve large portions of ordinary practice while treating mathematical objects in terms of what rational thinkers can coherently construct. Nik Weaver, for instance, has defended a rigorous “mathematical conceptualism.” (To be precise about his view: it is a form of predicativism — a program restricting mathematics to objects that can be built up without vicious circularity — rather than a claim that arithmetic depends on any particular person’s psychology.)


Its strength. Conceptualism explains how we know mathematics. If mathematical structures are intelligible constructions of the mind, no mysterious causal bridge to a remote realm is required; we participate directly in the activity from which mathematics arises. It also reflects real practice — mathematicians reason through definitions, constructions, and proofs, not by passively observing objects.


Its difficulty. Human minds are contingent, limited, and fallible. Would two plus two stop equaling four if every human vanished? Did no mathematical truth hold before the first rational creature appeared? A sophisticated conceptualist need not answer crudely — mathematical truth might be cashed out as what any suitable rational mind could construct, not what someone happens to be thinking. Still, the view must explain how mind-dependent concepts acquire necessity and universality without becoming hostage to contingent human psychology. It shortens the distance between knower and truth, but risks making eternal-looking truths depend on temporary minds.

4 · Theistic Conceptualism: Mathematical Truth Is Grounded in God

Theistic conceptualism agrees that mathematical truth is fundamentally related to mind — but denies that finite human minds are its ultimate foundation. Instead, logical and mathematical truths are grounded in the eternal intellect of God. Properties, propositions, possibilities, and mathematical structures are understood as divine ideas, or as realities functionally equivalent to ideas within the divine mind.

The view has deep roots. Augustine argued that numerical truths are not drawn merely from bodily sensation and do not change when human minds fail to grasp them; in On Free Choice of the Will he described the order and truth of number as stable, incorruptible, and common to all who reason. Modern versions are more technically developed — Greg Welty’s account of “theistic conceptual realism,” for example, treats at least some abstract objects as uncreated divine thoughts with an objective reality independent of finite thinkers.


Its strength. It aims to keep the principal virtues of both realism and conceptualism. Mathematical truths are objective because they don’t depend on human opinion; necessary because God’s nature and knowledge aren’t contingent; knowable because reality and the human mind ultimately proceed from the same rational source. The fit between mathematics and nature becomes less surprising, too: the structures through which the world is made and the structures the mind recognizes flow from one divine wisdom. Note that on most versions God does not arbitrarily decide that two plus two equals four; mathematical necessity expresses God’s unchanging rational nature rather than a decree that could have gone the other way.


Its difficulty. The view raises hard theological questions. Are divine concepts identical with God, or distinct entities within him? If distinct, does that threaten divine simplicity, or make God depend on something other than himself? If God creates mathematical truths, did he need logical possibilities already in place in order to create them? If he doesn’t create them, in what sense is he the source of all that exists? Contemporary philosophers of religion disagree over whether divine conceptualism truly protects aseity — the doctrine that God exists from himself and depends on nothing external. Indeed, one of the sharpest critics is a fellow theist: William Lane Craig, in God Over All, defends divine aseity precisely by rejecting the idea that abstract objects (even as divine ideas) exist alongside God. So Christian theism does not by itself settle the debate; Christian philosophers may be Platonists, nominalists, conceptualists, or defenders of some divine-ideas account.

In plain terms — aseity & simplicity

Aseity is the classic idea that God depends on nothing outside himself. Simplicity is the idea that God isn’t built out of separate parts. If eternal numbers sat beside God as things he didn’t make, that would seem to dent aseity — which is one reason some thinkers put mathematical truths inside God’s mind instead. But if they’re distinct ideas within God, that can seem to bump against simplicity. Theistic conceptualists spend a lot of effort threading exactly this needle.

Structuralism: Are Numbers Positions Rather Than Objects?

Another influential approach is mathematical structuralism. Structuralists argue that mathematics is chiefly about structures and the positions objects occupy within them, not isolated objects. The number two, for instance, may be understood as “the position after one and before three” inside the natural-number structure, rather than as an independent object with an identity detached from that structure.


Stewart Shapiro’s work has been especially important in developing this view. Structuralism can itself take realist or anti-realist forms, so it doesn’t simply replace the earlier debate — it reframes the question from “What kind of object is the number two?” to “What kind of reality does the natural-number structure possess?” That can clarify practice, but the underlying metaphysical question returns: are structures discovered, constructed, abstractly real, or grounded in mind?


Would Mathematical Truths Exist Without Human Brains?

The answer depends partly on what we mean by “truth.” With no human beings, there would be no English sentence “two plus two equals four,” no chalk marks, no textbooks, no human acts of calculation. But would the relationship the sentence expresses still hold?

  • The Platonist says yes, because mathematical objects exist independently.
  • The human conceptualist may say the truth concerns what rational agents could construct under suitable conditions, rather than an independently existing realm.
  • The nominalist may resist talk of a proposition existing without any thinkers, while still holding that any correctly built arithmetic would yield the same result.
  • The theistic conceptualist says yes, because mathematical truth remains eternally present to the divine intellect.

This surfaces a useful distinction between a sentence, a thought, and the reality or relation they express. Destroying every written expression of a truth does not obviously destroy what the expression was about. The stubborn intuition that mathematical relations would remain valid without us isn’t a proof of Platonism or theism — but it is evidence that ordinary mathematical thought is committed to an objectivity exceeding any particular brain.


Why Is Nature Mathematically Intelligible?

The status of mathematics would be puzzling even if it stayed inside textbooks. Its effectiveness in describing the physical world makes the mystery deeper. Equations developed through abstract reasoning often describe natural phenomena with extraordinary accuracy — not merely arranging past observations, but predicting events never before seen.


In 1960 the physicist Eugene Wigner famously called this the “unreasonable effectiveness of mathematics in the natural sciences.” He stressed that mathematical concepts keep turning up in unexpected physical settings and describing them with remarkable precision, even though the reason for this correspondence stays obscure. Wigner offered it as a profound puzzle — not as a proof of God. Several explanations are on the table.

Mathematics was developed from nature

Human mathematical concepts often begin in ordinary experience. Counting grows out of encountering distinct objects; geometry reflects spatial relationships; measurement comes from comparing physical magnitudes. No surprise, then, that tools abstracted from the world can be applied back to it. This explains some applicability — but perhaps not all. Highly abstract mathematics sometimes finds physical use long after its development, having been designed with no such phenomenon in mind.

We select the mathematics that works

Part of the apparent mystery may be a selection effect. Mathematicians have produced countless concepts; scientists keep the ones that model nature and quietly set the failures aside. The “surprising” effectiveness of the surviving mathematics can look larger once we ignore everything that didn’t apply. This is a genuine corrective — not every elegant theory describes the universe, and even successful models usually apply only within limited domains. Yet selection alone doesn’t make the fit trivial. You can only choose a tool that works if there’s already a deep enough structural correspondence for any tool to yield precise, testable predictions.

The physical world itself has mathematical structure

Perhaps mathematics succeeds because nature is genuinely ordered — models work because they capture real patterns, symmetries, quantities, and relations in the world. The intelligibility lies in nature, not in a mysterious transfer of human invention onto an alien reality. Plausible — but it relocates the question rather than dissolving it: why does the physical universe possess such stable, elegant, and discoverable structure?

The world proceeds from rational mind

The theistic explanation is that the universe is mathematically intelligible because it proceeds from divine wisdom. We can understand the world because both the rational mind and the ordered creation trace back to God; mathematics applies not by coincidence but because creation has an intelligible structure and human reason is able — however imperfectly — to recognize it. This has real unifying power, tying together mathematical necessity, human knowledge, and the order of nature in one vision.

It is not, however, a deductive proof of Christianity. A Platonist can affirm objective mathematical reality without God. A naturalist can argue that mathematics tracks physical structure. A nominalist can read its usefulness instrumentally. The force of the theistic argument is comparative, not mechanical. The question is whether a rational Creator makes the following conjunction less surprising:

  • necessary logical and mathematical truth,
  • finite minds capable of knowing it,
  • a physical universe deeply describable through it, and
  • a stable correspondence between thought and nature.

A Careful Argument from Logic and Mathematics

The argument should not be stated as a quick syllogism — “Numbers are immaterial; immaterial things require God; therefore God exists.” Nearly every step there needs defense: nominalists deny the first premise, and Platonists may deny the second. A more responsible version is abductive — an inference to the best explanation.

The argument, stated honestly
  1. Logical and mathematical truths appear objective, necessary, and not reducible to any particular physical inscription or brain state.
  2. Human beings possess genuine, if fallible, knowledge of these truths.
  3. Mathematical structures display an extraordinary capacity to describe the physical universe.
  4. Any adequate worldview should explain their objectivity, necessity, knowability, and applicability.
  5. Theistic conceptualism offers a unified account — grounding rational truths in an eternal mind, and physical order in that mind’s creative wisdom.
  6. Therefore, logic and mathematics provide some evidence for a rational, theistic foundation of reality.
In plain terms — what “abductive” means

This isn’t a proof like 2+2=4. It’s the reasoning a detective uses: given all the clues on the table, which single explanation makes the whole set least surprising? Abductive arguments raise or lower probabilities; they don’t force a conclusion. That’s why the honest verdict below is modest.


This argument does not establish every premise beyond dispute, so its conclusion should be stated modestly. Logic and mathematics do not march a person directly from arithmetic to the Christian doctrine of God. What they do is resist the assumption that reality is exhausted by concrete matter in motion. They suggest that truth is not merely something brains manufacture — that the universe is not only present to us as physical force, but open to rational understanding.


Theological Significance

Christian theology begins not with an impersonal mathematical realm but with the living God. The Gospel of John declares that all things were made through the eternal Word, the Logos (John 1:1–3). This should not be flattened into the claim that Logos simply means “logic,” nor was John offering a theory of abstract mathematical objects. The claim is larger: creation proceeds through the divine Word and wisdom rather than from ultimate irrationality. The world is not independent of God, and its intelligibility is not foreign to its origin.

Paul likewise writes that all things were created through Christ and for him, and that in him all things hold together (Colossians 1:16–17). Christian faith therefore reads the rational order of creation as dependent on the divine Son — not as a rival realm standing eternally beside God. Our minds do not contain or master truth; we receive the capacity to recognize an order that precedes us.

That capacity is finite. Mathematical genius does not remove human fallibility, and logical skill does not produce moral wisdom. Reason itself can be turned toward pride, manipulation, and self-deception. Yet its proper use is sacred: to reason honestly is to submit the mind to a truth it did not create.


Reflection

There is something quietly humbling about mathematics. A theorem does not bend to our preference. The law of noncontradiction does not soften because consistency has become inconvenient. Truth stays what it is while generations rise, argue, learn, and pass away. We enter a rational order that was already waiting for us.

The Christian need not treat every equation as a secret code proving God’s existence. Creation is not a puzzle designed to make faith effortless. Yet neither should we miss the wonder: frail, embodied creatures can lift their minds beyond the immediate world of hunger and danger and sensation to contemplate truths that seem timeless. We count because creation has order. We reason because reality is intelligible. We discover because truth is not our possession but our inheritance.

The deepest Christian response, then, is not intellectual triumph but gratitude. The eternal Word through whom all things were made has given human beings minds capable of seeking what is true. Every honest proof, every correction of error, every glimpse of hidden order can become an act of reverence. Mathematics may not lead every thinker to God. But for the Christian, its beauty is neither cold nor empty. It is one more sign that creation bears the imprint of wisdom — and that the human mind finds its rest not merely in knowing truths, but in knowing the One who is their everlasting source.




Editorial & fact-check note:

This piece is written to explain the debate fairly, not to overstate the case. The four positions are presented in the strongest terms their own defenders would use, and each is paired with its most serious difficulty — including the difficulties for the theistic view. Citations describe what each thinker argued; they are not endorsements of every claim.

Bibliographic details for the load-bearing sources were verified against primary and scholarly indexes prior to publication: Benacerraf’s “Mathematical Truth” (Journal of Philosophy 70:19, 1973, pp. 661–679); Wigner’s “Unreasonable Effectiveness” (Communications on Pure and Applied Mathematics 13:1, 1960, pp. 1–14; originally the 1959 Courant Lecture); Field’s Science Without Numbers (1980), which contains the “Newtonian Gravitational Theory Nominalized” chapter; Weaver’s “Mathematical Conceptualism” (arXiv:math/0509246, 2005); and Welty’s Oxford M.Phil. thesis (2000), later developed in his 2006 D.Phil. and in Beyond the Control of God? (2014).

Sources:

  • Anderson, James N., and Greg Welty. “The Lord of Non-Contradiction: An Argument for God from Logic.” Philosophia Christi 13, no. 2 (2011): 321–338.
  • Aristotle. Metaphysics, Book IV, esp. chs. 3–4. Trans. W. D. Ross.
  • Augustine of Hippo. On Free Choice of the Will, Book II, ch. 8.
  • Balaguer, Mark. Platonism and Anti-Platonism in Mathematics. Oxford University Press, 1998.
  • Benacerraf, Paul. “Mathematical Truth.” The Journal of Philosophy 70, no. 19 (1973): 661–679.
  • Craig, William Lane. God Over All: Divine Aseity and the Challenge of Platonism. Oxford University Press, 2016.
  • Field, Hartry. Science Without Numbers: A Defence of Nominalism. Princeton University Press, 1980; rev. ed., Oxford University Press, 2016.
  • Gould, Paul M., ed. Beyond the Control of God? Six Views on the Problem of God and Abstract Objects. Bloomsbury Academic, 2014.
  • Quine, W. V. O. “On What There Is.” The Review of Metaphysics 2, no. 5 (1948): 21–38. Reprinted in From a Logical Point of View. Harvard University Press, 1953.
  • Shapiro, Stewart. Philosophy of Mathematics: Structure and Ontology. Oxford University Press, 1997.
  • Weaver, Nik. “Mathematical Conceptualism.” arXiv:math/0509246, 2005.
  • Welty, Greg. An Examination of Theistic Conceptual Realism as an Alternative to Theistic Activism. M.Phil. thesis, University of Oxford (Oriel College), 2000. Further developed in Theistic Conceptual Realism, D.Phil. thesis, University of Oxford, 2006.
  • Wigner, Eugene P. “The Unreasonable Effectiveness of Mathematics in the Natural Sciences.” Communications on Pure and Applied Mathematics 13, no. 1 (1960): 1–14.
  • Zalta, Edward N. “In Defense of the Law of Non-Contradiction.” In The Law of Non-Contradiction: New Philosophical Essays, ed. Graham Priest, J. C. Beall, and Bradley Armour-Garb. Oxford University Press, 2004.

Topic: Philosophy