The Logic of Love: A Natural Theory of Morality

All you need is love, all you need is love,
All you need is love, love, love is all you need.
All you need is love (all together now)
All you need is love (everybody)
All you need is love, love, love is all you need.
~ The Beatles (1967)

This article presents an objective, naturalistic, scientific theory of morality. It is presented as an answer to the religious argument that there would be no objective morality without God and the equally fallacious secular argument that there is no objective morality at all. It is based on the same fundamental principles that have guided modern physicists to discover the unified laws of nature. To understand it, we first must review the essential nature of science and the historical trajectory that has led to the modern unified theories.

Objectivity, Symmetry, and Invariance

The essence of science is objectivity and the essence of objectivity is invariance under transformation. Harvard philosopher Robert Nozick explained this in his article Invariance and Objectivity where he describes the nature of objective facts or truths as follows:

  1. First, an objective fact is accessible from different angles. It can be repeated by the same sense (sight, touch, etc.) at different times, it can be repeated by different senses of one observer, and by different observers. Different laboratories can replicate the phenomenon.
  2. The second mark of an objective truth, related to the first, is that there is or can be intersubjective agreement about it.
  3. The third feature concerns independence. If p is an objective truth, then it holds independently of people’s beliefs, desires, hopes, and observations or measurements that p.
  4. An objective fact is invariant under various transformations. It is this invariance that constitutes something as an objective truth and it underlies and explains the first three features.

Nozick unified and grounded our concept of objectivity by explaining all its features in terms of a single concept – invariance under transformation. This commonsensical definition is the very root of why we believe there is an “objective world” independent of ourselves. We pick up an object, rotate it, look at it under different light, tap on it. We show it to others and ask what they see. Some properties remain invariant no matter how we or others investigate it; we call those properties objective facts.

Nozick’s definition of objectivity coincides exactly with the mathematical definition of symmetry. A geometrical object is symmetric with respect to a given transformation if its shape remains unchanged. The two most obvious symmetries are reflection and rotation. An object with bilateral symmetry looks the same when reflected in a mirror. An object with rotational symmetry looks the same when rotated through a given angle. For example, the appearance of a square remains invariant when it is rotated by 90o. A circle is the most symmetric of all two dimensional objects because it can be rotated through any angle without variation.

Symmetry principles have recently become the fundamental unifying concept of physics, as noted by theoretical physicist and Nobel laureate Steven Weinberg:

Symmetry principles have moved to a new level of importance in this century, and especially in the last few decades: there are symmetry principles that dictate the very existence of all the known forces of nature.

Countless physicists have chimed in with similar observations. For example, Christopher Martin, in his article On Continuous Symmetries in the Foundation of Physics says this:

It is difficult to overstate the significance of the concept of symmetry in its many guises to the development of modern physics. Indeed, on could reasonably argue that twentieth-century physics with its pillar achievements of successful physical theories of spacetime/gravitation and the electromagnetic and nuclear interactions merits calling that century the “Century of Symmetry.” For symmetry played a key part in each of these developments.

To understand the profound significance of these statements, we need to briefly review the history of physics.

Unification and Symmetry: The Historical Trajectory of Science

Scientific theories are designed to give a comprehensive explanation of a body of facts in terms of a few elementary principles. Successful theories reveal the underlying unity of apparently diverse phenomena. A Theory of Everything, often called the Holy Grail of physics, would give a fully unified explanation of all physical phenomena within a single theoretical framework based on a small set of axioms. If found, it would be a solution to the sixth of the twenty-three unsolved problems listed by mathematician David Hilbert in 1900. He suggested that physics should be axiomatized much as Euclid established the theory of Geometry on five axioms in his Elements (ca. 300 BCE). Isaac Newton made the first great step towards solving Hilbert’s sixth problem when he laid the axiomatic foundation of Classical Mechanics in his Three Laws of Motion:

  1. An object remains at rest or moves in a straight line with constant velocity v unless acted on by a force F.
  2. The force F is equal to the rate of the change in momentum (mv). For a body of constant mass m, the acceleration a is related to the force F by the equation F = ma.
  3. For every action caused by force F there is an equal and opposite reaction given by -F.
Maxwell’s Equations

These three simple laws (principles, axioms) unified our understanding of the motion of objects, enabling us to both explain and predict related facts. But there were other phenomena such as light, electricity, and magnetism that required their own independent explanations so physicists were stuck with four disparate theories: a theory of mechanics, a theory of light, a theory of electricity, and a theory of magnetism. This all changed in 1861 when James Clerk Maxwell unified the latter three in a single theory of Electromagnetism that required only four elegant and compact axiomatic equations. There now were only two theories that required unification – Electromagnetism and Newtonian Mechanics.

The unification of Newtonian Mechanics and Electromagnetism was a daunting problem because the two theories are invariant under different transformations that are not consistent with each other. They could not both be true without contradicting the definition of objectivity, the very heart of science. Newtonian Mechanics is invariant under Galilean transformations whereas Electromagnetism is invariant under Lorentz transformations. To resolve this problem, Einstein focused on the fact that the speed of light, c, was itself a constant (invariant) in Maxwell’s equations, and so concluded that it was Newtonian Mechanics that must be modified to be Lorentz invariant. The result was his Special Theory of Relativity which not only unified Mechanics and Electromagnetism, but also unified space and time into a single ontological unity – spacetime. In the words of Minkowski:

Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality.

And of course the central equation of Einstein’s new theory, e = mc2, revealed the underlying unity of energy and matter. This shows the power of symmetry principles: At a time time when most people were still traveling in horse and buggy, Einstein revolutionized our understanding of space, time, mechanical motion, and energy by revealing their unity based on symmetry. This harkens back to the Plato’s understanding of symmetry, which he said “creates the greatest unity possible” as noted in the introduction to Symmetries in Physics : Philosophical Reflections:

Symmetry is an ancient concept. Its history starts with the Greeks, the term summetria deriving from sun (with, together) and metron (measure) and originally indicating a relation of commensurability (such is the meaning codified in Euclid’s Elements, for example). But symmetry immediately acquired a further, more general meaning, with commensurability representing a particular case: that of a proportion relation, grounded on (integer) numbers, and with the function of harmonizing the different elements into a unitary whole: “The most beautiful of all links is that which makes, of itself and of the things it connects, the greatest unity possible; and it is the proportion (summetria) which realizes it in the most beautiful way” (Plato, Timaeus, 31c).

Harmony, unity, beauty, science, and objectivity are themselves all subsumed in the concept of symmetry. These qualitative concepts became quantitative in 1918 when Amalie Emma Noether published her theorem that proved that any symmetry of spacetime would have a corresponding conserved quantity. Suddenly all the conservation laws of physics such as conservation of linear momentum, angular momentum, and energy, were derived from first principles. Anthony Zee expressed his excitement at this discovery in his fabulous review of this topic called Fearful Symmetry:

Conservation of energy, momentum, and angular momentum are among the first laws that one learn when studying physics. Together, they govern the movement of everything in the physical universe, from the collision of galaxies to the whirl of the electrons in atoms. For years, I did not question where these conservation laws came from; they seemed so basic that they demanded no explanation. Then, I heard about Noether’s insight and I was profoundly impressed. The revelation that these basic conservation laws follow from the assumption that physics is the same yesterday, today, and tomorrow; here there and everywhere; east, west, north, and south, was for me, as Einstein put it, essentially spiritual.

Einstein used the same principles to unify our understanding of Gravity by extending his principle of relativity to include general covariance of the laws. Quantum physicists followed his lead and now all physics is based fundamentally on symmetry principles. Space prohibits further review. It suffices to note that the trajectory of physics has been one of discovering ever greater unity based upon symmetry. This is the same pattern that I follow in my theory of morality.

The Logic of Love: A Natural Moral Theory

Love is the only sane and satisfactory answer to the problem of human existence. The full answer lies in the achievement of interpersonal union, of fusion with another person, in love.
~ The Art of Loving by Erich Fromm (1956)

The moral theory I propose is intended to be objective in the same sense as our theories of physics described above. Therefore we must begin, like Einstein, to see if there are any invariant moral principles. The answer is not long to find. If there is any invariant moral principle, it is the Golden Rule. Here are a few examples from all over the planet:

Christianity All things whatsoever ye would that men should do to you, do ye so to them; for this is the law and the prophets. Matthew 7:1
Confucianism Do not do to others what you would not like yourself. Then there will be no resentment against you, either in the family or in the state. Analects 12:2
Buddhism Hurt not others in ways that you yourself would find hurtful. Udana-Varga 5,1
Hinduism This is the sum of duty; do naught onto others what you would not have them do unto you.Mahabharata 5,1517
Islam No one of you is a believer until he desires for his brother that which he desires for himself. Sunnah
Judaism What is hateful to you, do not do to your fellowman. This is the entire Law; all the rest is commentary. Talmud, Shabbat 3id
Taoism Regard your neighbor’s gain as your gain, and your neighbor’s loss as your own loss. Tai Shang Kan Yin P’ien
Zoroastrianism That nature alone is good which refrains from doing to another whatsoever is not good for itself. Dadisten-I-dinik, 94,5

Now look at the principle itself – it is symmetric under an interchange of Self and Other! This means our search for invariance has led to a principle that is itself symmetric. If this isn’t the Holy Grail of Moral Theory, I don’t know what could be.

There is another invariant associated with morality: Love. A person with no love is a person with no morality. Furthermore, love is the “motive force” in all moral reasoning. This is most evident in the formulation of the Golden Rule attributed to Jesus, “Thou shalt love thy neighbor as thyself.” And what is the nature of love? It is closely related to, if not identical with, the concept of unity. It is a kind of symmetry. Thus we arrive at my objective moral theory which is based on two symmetrically related axioms and two ontologically primitive concepts: Self and Love:

  1. Self Love: This is the axiom that a Self loves Self because Self is one by definition. A Self naturally desires its own well-being. For a Self to exist, it must be a unified integrated whole.
  2. Moral Symmetry: A rational Self recognizes the Other as a Self like unto one’s own Self. Moral symmetry stems from Logic and Love. Love is the unity of Self and Other. Self Love is reconciled with Love of the Other through the symmetric logic of the Golden Rule. The principle of indifference implies that there is no justification to prefer Self over Other. This is the principle of moral symmetry, fairness, justice. All moral statements must be symmetric under an interchange of person A and person B.

The first axiom is analogous to Aristotle’s law of identity: A is A. Identity is necessarily unity and the simplest symmetry. The second axiom symmetrically relates Self and Other. Fairness and justice are the root of morality, so morality is  intrinsically objective, like a pair of scales. It is my assertion that these two axioms explain all our moral intuitions. Therefore, this theory is scientific in the sense that it can be falsified if we find moral intuitions that it contradicts or fails to explain. It is an objective, naturalistic, scientific theory of morality.

Both principles are founded in the most basic and universal moral intuitions shared by all humanity and any objection is immediately shown to violate one of the two principles. The Golden Rule (Reflective Love) stands above all other moral principles as explained by Professor R. M. MacIver in his article The Deep Beauty of the Golden Rule (provided online by Google Books):

Do to others as you would have others do to you. This is the only rule that stands by itself in the light of its own reason, the only rule that can stand by itself in the naked, warring universe, in the face of the contending values of men and groups.

There also is another approach that really gets to the heart of the matter. My argument is a “left brained” analytic approach to morality. The “right brained” holistic approach is much simpler. It subsumes both principles in a single concept – Universal Love for all sentient beings. This is an objective standard because any rational observer could, in principle, discern between what is or is not more loving. To refute this argument, it would have to be shown that people cannot objectively determine what is more loving. Put together, we have a “whole brained” approach to the understanding objective morality:

Left Brain, Analytic
Right Brain, Holistic
1) Self Love: All rational beings desire the best for themselves.
2) Reflective Love: Moral symmetry, fairness, do unto others as you would have them do to you.
Universal Love for all sentient beings.

Despite its clarity, many theists will attempt to refute the analytic form of my argument because it defeats their moral argument for God. This is a great irony because the two principles were taught by Christ when he said “Thou shalt love thy neighbor as thyself” (Matthew 22:39). His statement includes both principles of Self-love and the Golden Rule, and is best described as Universal Love so it encompasses both forms of my argument. Another irony leaps out when Christians oppose the analytic form because they unwittingly imply that they lack love for others when they say that there would be no morality without God. They forget love – the first principle of morality – when they argue that morality is based on mere rules dictated by a god.

Some people may be confused by the first principle because they have been taught that self-love is contrary to love for others. Nothing could be further from the truth. On the contrary, loving others is impossible without self-love. American psychologist Erich Fromm eloquently explained this in his book The Art of Loving. He was a masterful logician of love. His book has been hailed as one of the most important of the Twentieth Century. Fifty-six years ago he isolated and articulated the two axioms of my objective theory of morality. I was thrilled to find his work after I had formulated my theory. Here is the relevant extract from his book (pg 58). He first clarifies the illogical conflation of self-love and selfishness, and then explains the Golden Rule:

These questions arise: Does psychological observation support the thesis that there is a basic contradiction and a state of alternation between love for oneself and love for others? Is love for oneself the same phenomenon as selfishness, or are they opposites? Furthermore, is the selfishness of modern man really a concern for himself as an individual. with all his intellectual, emotional, and sensual potentialities? Has “he” not become an appendage of his socioeconomic role? Is his selfishness identical with self-love or is it not caused by the very lack of it?

Before we start the discussion of the psychological aspect of selfishness and self-love, the logical fallacy in the notion that love for others and love for oneself are mutually exclusive should be stressed. If it is a virtue to love my neighbor as a human being, it must be a virtue—and not a vice—to love myself since I am a human being too. There is no concept of man in which I myself am not included. A doctrine which proclaims such an exclusion proves itself to be intrinsically contradictory. The idea expressed in the Biblical “Love thy neighbor as thyself!” implies that respect for one’s own integrity and uniqueness, love for and understanding of one’s own self, can not be separated from respect for and love and understanding of another individual. The love for my own self is inseparably connected with the love for any other self.

We have come now to the basic psychological premises on which the conclusions of our argument are built. Generally, these premises are as follows: not only others, but we ourselves are the “object” of our feelings and attitudes; the attitudes toward others and toward ourselves, far from being contradictory, are basically conjunctive. With regard to the problem under discussion this means: Love of others and love of ourselves are not alternatives. On the contrary, an attitude of love toward themselves will be found in all those who are capable of loving others. Love, in principle, is indivisible as far as the connection between “objects” and one’s own self is concerned. Genuine love is an expression of productiveness and implies care, respect, responsibility, and knowledge. It is not an “affect” in the sense of being affected by somebody, but an active striving for the growth and happiness of the loved person, rooted in one’s own capacity to love.

From this it follows that my own self, in principle, must be as much an object of my love as another person. The affirmation of one’s own life, happiness, growth, freedom, is rooted in one’s capacity to love, i.e., in care, respect, responsibility, and knowledge. If an individual is able to love productively, he loves himself too; if he can love only others, he can not love at all.

Fromm hammered this point home on page 63 where he quoted Meister Eckhart as stating that absolute symmetry between Self and Other is required for true love, which is unity:

These ideas of self-love cannot be summarized better than by quoting Meister Eckhart on this topic “If you love yourself, you love everybody else as you do yourself. As long as you love another person less than you love yourself, you will not really succeed in loving yourself, but if you love all alike, including yourself, you will love them as one person and that person is both God and man. Thus he is a great and righteous person who, loving himself, loves all others equally”

This is the logic of love. Our moral intuitions are fundamentally based on love for Self and Other modulated through the symmetric logic of the Golden Rule.

The Beatles got it right. All you need is love.

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  1. Posted January 15, 2013 at 5:14 pm | Permalink

    Why not mail some of your points/arguments to Dr. William Lane Craig @ Reasonable Faith?

  2. Posted January 15, 2013 at 5:20 pm | Permalink

    Hi Daniel,

    I’m in the process of writing a more formal refutation of his central argument. I will notify him when it is done.


  3. Posted February 6, 2013 at 2:50 am | Permalink

    Hi Richard:
    You said:
    Despite its clarity, many theists will attempt to refute the analytic form of my argument because it defeats their moral argument for God. This is a great irony because the two principles were taught by Christ
    But you don’t believe Jesus the Christ existed? Or is it that you believe Jesus existed but Jesus is not Christ aka GOD!? Your inter-changing of terminology is very confusing…



  4. Posted February 6, 2013 at 1:07 pm | Permalink

    Hey there Mystykal,

    I understand your confusion. When I refer to something attributed to Jesus in the Bible, I often use the shorthand and say “as Christ taught.” That is not meant to imply that I think the record is accurate. I just don’t like to clutter my comments with “as attributed to Christ in the Bible.”

    I don’t have an opinion about the historicity of the man Jesus. I am pretty sure that the Biblical record cannot be accepted at face value since the Gospels contradict each other. For example, the parallel passages which clearly refer to a single event often record him saying different words so we don’t even know what he actually said. I talk about this in my forum post What did Jesus really say?. And more significantly, the Gospels differ on fundamental issues like the sequence of events and even the length of his ministry (the Synoptics say one year, John says three years).

    These issues are not too important if we don’t try to interpret the Bible as a literal historical record. Many scholars, such as John Dominc Crossan, see the the Gospels more as parables and “sacred myth” than historical records.

    Great chatting,


  5. Posted January 15, 2014 at 11:42 am | Permalink

    We have been debating on Facebook. Let me post my last comment here as well, more or less – as you may like to have some input on your blog as well.

    The idea of Self-love as the foundation of all love seems to be your essential premise, but it is one that I find very implausible.

    Many human qualities are totally asymmetric on my view – love being the obvious example. Self-love as you describe it sounds to me like a “new age” thing. In the West, the idea may have been grafted incorrectly on this Christian formulation “loving your neighbor as yourself” – which is being read as if it is necessary to love yourself first, otherwise you cannot love the other. But I think that biblical phrase was better represented by Martin Buber when he translated it as “love your neighbor as someone like yourself”. There is no specific reference to self-love there as far as I see. There is also Paulus in Ephesians 5 saying “no one ever hated his own body, but he feeds and cares for it”, but here the analogy seems to be in the ‘caring’, which is then assimilated with love – but still that doesn’t imply the need to “love yourself” (your premise). The comparison with ‘caring’ (for our own body) remains valid, but love is much more than caring. The body must be cared for, so it functions properly. Within this material engine, love can be ‘processed’ (through the mind), and this is a process that happens in all its irrational and asymmetric complexity. It may end up in a physical experience of making love, but it may also work in the sense of compassion – to name just two major ‘directions’ of love.

    There are no doubt many interesting aspects to holistic ideas, but how “whole” (complete) exactly someone experience is will still depend on what’s underneath these ideas. There are a few basic observations to make here:

    (a) Human beings may not be “whole” at all – this in contradiction to some Christian idea of (original, or newborn) perfection. Human beings may be a “crooked wood” (Immanuel Kant), in need of “becoming who they are” (Nietzsche), but never really being complete.

    (b) On the other hand, even if human beings would be “whole” (complete), does that make them good? Being right or being complete doesn’t make a person good all by itself. Idealism, perfectionism, even romanticism can be quite disturbing in human relations. They may prevent someone to be a forgiving person, for instance. Maybe ‘perfect people’ (whatever that means) are potentially the least human(e) ones.

    Self-love may be an aspect of love, but I tend to see it as just some side-effect of it. I once honestly asked myself the question: do I really need to “love myself” as people always keep saying? And I ended up concluding that I didn’t even know what they meant by that. In my experience, to love others generates a realm of shared love that makes the lover feel part of it as well – this is not “self-love” as far as I see. What people perceive as “self-love” may just be an idea they have in their head, which in reality means something like ‘caring’ for yourself, not really ‘loving yourself’. It occurs to me that “loving yourself” is not really love.

  6. Matthjar
    Posted July 30, 2014 at 1:39 am | Permalink

    What an outstanding Theory I Love it ..;-)… It makes total sense to me in almost every aspect…….

    It seems to be just another way of stating Gods Plan of Salvation, specially if someone like myself believes that God=Love.

    At this point we need to ascertain that while this has been an bedrock instruction from every major religion and common knowledge for all of recorded history then why do we not have a more Loving and Moral World. There seems to be some disconnect from the theory part or this idea to the actual Practice or Nuts and Bolts of this amazing Idea.

    Here are some ideas that i would like to bounce off you…..

    1. With Two axioms of Self Love and Moral symmetry (best described as Unity) it could be that in all Truth we need to come to the realization that the concept of the Self and the the concept of the Other is actually an illusion and that there is NO real difference between the Self and the Other. The inability to let go of our individual identity prevents us from psychologically releasing the illusion that Our Self is actually One and the same as the Other, only manifest in 2 different physical bodies.

    A. A Point that provides a clue that this hypothesis might actually be correct. In the act of Physical Love the orgasm very often is accompanied by complete loss of the sense of Self and the sense of the other. This is why the orgasm is often referred to as the “little death.” So a very short period of time we get a very small taste of possibly a higher reality and are able to drop the illusion. If one was able to see the Other as the Self and vice versus then it would be much more practical to continously follow this Morality to its fullest extent in the love of the SelfOther. Also possibly that with more practice we can reach a more enlightened stage and experience this same effect not only on a physical level but on an emotional and ultimately a spiritual level also.

    2. If we accept the premise that God=Love then it could be that as more and more people undergo the process of Salvation and receive the indwelling of God from within there very beings that by being so filled with this Ultimate and Powerful form of Love it would be impossible to contain and keep it from sloshing all over the Others around us as “Our Cup runneth over.” As the number of people in this state reaches a hypercritical mass or a tipping point the avalanche becomes unstoppable until under the premise of Love begats Love the vast majority are practicing this new morality. The process of Forgiveness would be widely practiced allowing perceived and real transgressions to be uprooted before the can reach maturity and go to seed halting the cycle of Hate Bitterness and Evil.

    It is possible to truly unlock the full potential of this way to achieve a Just Moral Society requires a complete Trust in the Power of Love (God??)

    Looking forward to your responses to these ideas even though i realize the second one kinda defeats your whole purpose of trying to have morality with out God…. but it is possible that it matters little what you call IT as long as you fully embrace and Trust in its Power. :-).

  7. Posted July 15, 2015 at 2:25 pm | Permalink

    I have realized some points through your blog post. One other stuff I would like to state is that there are lots of games out there designed in particular for toddler age little ones. They incorporate pattern acknowledgement, colors, creatures, and designs. These normally focus on familiarization instead of memorization. This helps to keep children and kids occupied without having a sensation like they are learning. Thanks

  8. Adam
    Posted July 25, 2016 at 12:37 am | Permalink

    Dear Richard

    I’v a christian friend who insists that since we ‘intuit’ love – God must exist.
    (this reminds me of W Craig’s ‘apprehend’ moral relm)
    Any thoughts please?


  9. Posted July 30, 2016 at 7:37 am | Permalink

    Hi Adam,

    I would need to know more details to comment. Why would a human feeling like love or hate or jealousy or compassion imply the existence of a god?


2 Trackbacks

  • By Does the Bible lack Moral Integrity? on January 12, 2013 at 10:44 am

    […] The lack of ethical and moral integrity in the Bible is obvious from just the sampling of verses that I have presented, because they all have one thing in common – an absence of concern for the well being and flourishing of the human community – this disqualifies and thus invalidates much of the Bible, showing it cannot be used as an ethical judge or moral guide. This then brings one to the question of where does moral integrity come from. I have covered this subject to some degree in my article titled Biological Foundations of Morality. Another excellent article written by my husband can be found here: Logic of Love: A Natural Theory of Morality. […]

  • […] As discussed in my article On Integrity as the Highest Value, the concept of integrity unifies all science, philosophy, and knowledge. Ontology is based on the integrity of being. Logic is based on the integrity of thought. Epistemology is based on the integrity of knowledge. The concept of integrity is the universal solvent that loosens the most impenetrable philosophical conundrums. Case in point: morality is fundamentally ontological. It is based on what it means for something to be, to exist. As a first approximation, anything that threatens the integrity of being is judged to be evil, and anything that enhances the integrity of being is judged to be good. Moral judgments are objective because the integrity of being is an objective fact, and so we have objective definitions for both moral agency and moral judgments. I outline these ideas in my article The Logic of Love: A Natural Theory of Morality. […]

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