THE FOURTH DIMENSIONAND THE PRINCIPLE OF LEAST ACTION: Why the Clock Says “Tick-Tock”

It has been suggested that two major themes of this website are now converging in such a way that each throws light on the other – namely, the Fourth Dimension, and the Principle of Least Action. The following essay aims to explain this connection. This may in turn throw special light on the discussion of Karl Marx, the final stop on our Dialectical World Tour – coming next!

WHAT IS “MOTION”?

Least Action – whatever our understanding of this challenging term – is certainly a way of characterizing natural motion. Natural systems, the principle asserts, move in such a way that their action shall be least. Before we concern ourselves with the mystic term action, we might do well to focus on the no less mysterious term, motion. Not only will this help us to understand the intent of the principle, I think it will lead us to see a deep link between the Principle of Least Action, and the Fourth Dimension.

What, then, is motion? We moderns tend to think of it in instrumental terms – as the means of getting from intention to accomplishment: in between planning to be something, and actually being that intended thing. In this view, motion is a sort of intermediate, between intent and accomplishment: something to be gotten over, usually as quickly as possible. “Time is money,” we say – meaning, a cost. This colorless idea time accords with the mathematical view of time as a line: our lives pass along this continuum from goal to goal, the moments between, mere means, to be passed through as expeditiously as possible. Time is money, we say, meaning cost. This uniform, colorless continuum Newton mastered by finding a way to measure motion at a point, as if the now were its dwelling-place. Taking this to the limit, he gave us the mathematics of conventional physical science: the differential calculus. Absolute, mathematical time, Newton was sure, flowed calmly through absolute space, in God’s divine sensorium.

As so often happens, the ancients had a different, more interesting point of view, suited to a richer and wiser concept of Nature itself. Calling Aristotle as our witness, we’re told that being does not lie merely at the two ends of a span of intervening motion. Rather, being inheres in the notion itself. There, in that very motion, we find ourselves in the fullness of our being. As we might expect, Aristotle has a word for this. energeia: being-at-work. And since the work is at every stage shaped to its end – its TELOS – we can call this richer, organic concept of living, EN-TELECHY.

Rest assured, this old view is by no means a threat to modern science. Leibniz, already in Newton’s time, was developing a more complex form of the calculus suitable to this richer view of motion. Instead of zeroing-in on the passing moment, it looks to the whole span of the motion, from inception to closure. It’s called the integral calculus. In its variational form, it weights every moment with respect to the goal, and hence meets Aristotle’s test of entelechy. Whether it’s a radiating atom or a busy mouse, every stage of its motion is inherently – by Nature – shaped to its goal. The motion, then, is truly whole.

Aristotle goes on to say a funny thing about time. Time, he seems to say, is the number of motion(s). To clarify, he illustrates by saying we count the number of times the horse goes around the track. More generally, in the order of being, first there is the race, and then, secondarily, we count the laps, and time arises. The whole, which is the motion, is primary; motion doesn’t happen in time. Being comes first; time is merely the count of the generations of being.

Come to think of it, that’s the way we encounter time in daily life. Our encounter with time is mediated by some motion: we count the clock which tells the time. That’s why the classic clock says, tick-tock. The swings of its balance are counted by ah escapement, going first tick, and then tock, to mark the completion of one cycle: one motion The time it tells is the count of its motions. More modern clocks, it is rue, speak in other voices, but they’re all counting motions of some sophisticated sort.

HOW THE FOURTH DIMENSION UNDERLIES LEAST ACTION

If we’re satisfied that a motion is essentially whole, we’re ready to turn to Least Action. All the natural world runs on the Principle of Least Action, so this is important to know about. Here is the Principle: Every natural motion, atom or mouse, unfolds in such a way that over the whole motion, total “action" will be least. Think of “action”, then, as activity-summed-over-the whole motion. Action thus refers to something Newton missed. Contra Newton, you can’t have action at a moment! More positively put, nature accomplishes the overall goal with the least possible fuss. There’s a “good reason” for that; fuss (haste) makes waste. Every activity entails heat-loss (that’s why our bodies run so hot). The horse will ultimately run at top speed, but getting-up-to-speed will be accomplished by nature as gradually as possible. In turn, once up to speed, the myriad processes throughout he body will themselves run, collectively (organically), in such a way hat the speeding horse will be expending as little energy over each cycle of the gait, as possible.

If we image a running horse by means of a three-dimensional snapshot, we’ll evidently miss Nature’s point. We need to see that motion whole: each whole cycle of the gait as one single image. Our three dimensions are not enough: we must add a fourth axis to our image. In addition to our three spatial axes, we need a time axis as well. The resulting image will then encompass in a single geometrical figure the motion as that whole which, by its very nature, it is.

Though such four-dimensional imaging can indeed present this wholeness effectively to our physical eye, a larger aim must remain: through this visual experience, to extend this same insight to the eye of the mind. We might then perceive all natural motion in this four-dimensional way – and thus, in turn, achieve a larger grasp of the wholeness of that motion of ultimate interest, life itself.

Mathematical physics has widely accepted the Principle of Least Action as its basis. Taking the term physics in its old, true meaning, as the science of all nature – the fall of a leaf, or the beat of a heart – it’s nice to know that the more modern the science, the more it attests to wholeness, and to the richness of every moment: not as transient as it may seem.

What is “Action”, that Nature Should be Mindful of It?

We have been tracing the course of the book, NEWTON/MAXWELL/MARX by way of a dialectical tour of three worlds of thought. We have seen Maxwell replace Newton’s “Laws of Motion” with the Principle of Least Action as the foundation of the natural world. Here, we seek the meaning of this curious phrase, Least Action.

Let’s grant that Maxwell – along with perhaps most of the mathematical physicists of our own time – is right in supposing that the Principle of Least Action governs all the motions of he physical world. How can we make sense of this truth? What is Action, and why is essential that it be Least?

First, we must begin by recognizing nature is not inert, but in some sense purposeful: every motion in the natural world (and that includes practically everything we can point to, once we take our hands off the controls!) will begin with a goal (Greek TELOS). Think, for example, of that complex process by which an acorn develops into a flourishing oak. This Motion will unfold in such a way that its goal will be achieved in the most efficient way possible. Sound like good economics? We’re asked to see every natural motion as directed to some goal, and as unfolding in such a way that waste or loss en route be the least possible under the given circumstances.

This principle can be expressed elegantly in mathematical terms, rather esoteric and belonging to the hushed domain of mathematical physics. But since it is actually in play everywhere around us, in actions going on at all times, it’s time we reclaimed it and demanded to know what it means. Let’s make a serious effort here to understand the implications that the physicists – Maxwell chief among them – have been saying.

For Maxwell, the true paradigm of physics is the laboratory of Michael Faraday, working immediately with phenomena and tuned always to hear, without complication of intervening symbols, the authentic voice of nature. The Principle of Least Action is about the world we live in.

However we may distort and engineer it, it is always nature, ever-active, with which we begin, and our projects end. We may think we begin with a tabula rasa and design with total mastery to purposes of our own, but every blade of grass, infinitely quantum-mechanical-wise, will laugh at us. It is in the fields and the mountains, the atmosphere and the oceans, and the endlessly-complex workings of our own bodies, that Nature’s economics is inexorably unfolding. High time, that we take notice of it!

We begin always with some process – the fall of a stone, from cliff’s edge to the beach below or the slow unfolding of an acorn into a flourishing oak. The principle applies in every case. Further, nature thinks always in terms of the whole process as primary: the economic outcome cannot be conceived as the summation of disparate parts, however successful each might seem in its own terms.

The unifying principle throughout any motion is always its TELOS, and it is this which in turn entails an organic view of the motion as one undivided whole process. Each phase of the motion is what it is, and does what it does, precisely as it contributes to the success of the whole. If this seems a sort of dreamland, far from practical reality, we must remind ourselves that we are merely rephrasing a strict account of what Nature always does! Things go massively awry (the seeding gets stepped on by the mailman) but these events are external constraints upon the motion: under these constraints, the Principle holds, strictly. Ask any oak tree, blade of grass, or aspen grove. Each has endured much in the course of its motion, yet each has contributed, to the extent possible, to the success of the ecology of which it is a part.

Economic achievement of the goal, we might say, is Nature’s overall fame of mind. Within this frame, exactly what is the economic principle at work? Everything moves in Nature in such a way that Action over the Motion will be least.

So, what is action? Action is the difference, over the whole motion, between two forms of energy: kinetic and potential Nature wants that difference to be minimal: that is, over the whole motion, the least potential energy possible to be expended, en route, as kinetic – i.e., as energy of motion. (One old saying is that Nature takes the easy way.) Or we might suggest: nature enters into motion gracefully.

Think of the falling stone: the stone at the edge of a high cliff has a certain potential energy with respect to the beach below. That potential is ready to be released – converted into kinetic energy, energy of motion. Thus the TELOS is given: to arrive at the beach below, with that high velocity equivalent to the total potential with which the fall began.

Our principle addresses the otherwise open question, how exactly to move en route? There is just one exact answer: the rule of uniform acceleration – steady acquisition of speed. Galileo discovered the rule; Newton thought he knew the reason for the rule. But Maxwell recognized that Newton was wrong, and we need now to get beyond this old way of thinking.

The real reason for the slow, steady acceleration is that the final motion, which is the TELOS, be acquired as late in the motion as possible, and thus that total-kinetic-energy-over-time be least.

Our principle may turn out to be of more intense interest to biologists than to physicists, as the ”kinetic energy” in this case becomes life itself. The seed bespeaks life in potentia. The ensuing show, steady conversion of potential—its gradual conversion to living form as the seedling matures – is the growth of the seeding, the biological counterpart of the metered, graceful fall of the stone.

Our principle governs the whole process of conversion: the measured investment of potential into kinetic form defines the course of maturation. Nature is frugal in that investment: the net transfer of energy-over-time is minimal; transfer in early stages of growth is avoided. Growth, like the fall of the stone, is measured, and graceful. Growth is organic in the sense that every part of the plant, at every stage of the way, is gauged by its contribution to the economic growth of the whole plant.

As it stands, our analogy to the falling stone may be misleading. It is not, of course, the case that the seed holds in itself (like loaded gun!) the potential energy of the oak; the case is far more interesting. The acorn holds in its genome the program for drawing energy from the environment in a way which will assure Least Action over the whole growth process. Once again, frugality reigns, since that energy not drawn-upon by the seedling will be available to other components of the ecology. Since the solar energy is finite, whatever is not used by one is available to the others.

We are ready now to ask in larger terms, “What sense does it make, that Nature be thus frugal in expending potential energy – minimizing its “draw” upon potential in early stages of growth, though total conversion by the end of motion be its very TELOS?

The question is a difficult one, touching on the very concept of life itself. Here, however, is my tentative suggestion. Let us consider Earth’s biosphere as a newborn project, awaiting Nature’s design. Our Earth (like, no doubt, countless other “earths” in Nature’s cosmic domain) is favored with a certain flux of energy, in the form of light from our Sun: just enough, on balance, to sustain water in liquid form, one criterion, at least, for the possibility of life. With regard to Earth, then, Nature’s overall TELOS may reasonably be characterized as the fullest possible transformation of sunlight into life. Earth also offers a rich inventory of mineral resources, which Nature will utilize to the fullest, over time, in the achievement of this goal.

Might we not think of this immense process, still of course very much ongoing, in the terms we’ve used earlier – as one great motion, transforming as fully as possible the potential energy of sunlight, into the living, kinetic energy of life? (It might be objected that the flux of solar energy is kinetic, not potential. It is so in space, en route, but is made accessible as potential by that immense solar panel, the green leaf system of the world – which by its quantum magic captures photons, uses them to split water, and thus generate the electrochemical potential on which the motion of life runs.)

That said, we may apply the logic of Least Action to life on every scale: life’s TELOS is to encapsulate our allotted solar potential energy in living form, always by way of the most frugal path possible. What is saved by the Least Action of one life-motion, is grist for the mills of others – so that overall, the solar flux is utilized as fully as possible. “As fully as possible” at this stage: but the long, slow motion of evolution continues – always, no less governed by Least Action, towards a TELOS we cannot envision, yet of which we must be organically a part, today.

For an expansion of this concept, you can read an earlier lecture: The Dialectal Laboratory: Towards a Re-thinking of the Natural Sciences

NEXT: Karl Marx and his place in Newton/Maxwell/Marx.

THE PRINCIPLE OF LEAST ACTION

First Principle of the Natural World

It’s with a certain sense of awe that I introduce a new page on this website, to be devoted to the Principle of Least Action. I’ve written about this principle, on this website (see the article here) and elsewhere, in various ways and contexts, but it appears now for the first time as the centerpiece around which writings on this theme will be gathered.

The principle itself, though simple, requires careful statement, before we do that, however, we must pause to take the measure of situation. Even as leading physicists and mathematicians have embraced Least Action as the single moving principle of the entire natural world, most others, even at the highest levels of education and professionalism in fields other than mathematics or the physical sciences, regard it as of no interest to themselves, or more likely, have never heard of it all.

The issue is acute: our old conceptions speak of mechanism, with even the most subtle of natural bodies composed ultimately of inert parts moved by impressed forces, according to equations knowable only to experts. What a different picture Least Action paints! Wholeness is, in truth primary, with causality flowing from whole to part, not from part to whole. Nature is everywhere self-moving, and throughout, life is real. In short, the era of Newton is behind us, and once again, nature lives! We cannot know yet, what the consequences of embracing this truth might be: but the time to begin exploring this question is surely now, before we have altogether destroyed this planet–the living system of which we are all organic parts, and on which our lives depend. It’s the mission of this web page to explore the concept of least action, and some of the many ways it may affect our institutions and or lives. Such a trajectory of thought, which I would call dialectical, has been the theme of the ongoing blog commentary on  Newton/Maxwwell/Marx. Between Newton and Least Action, we may be living in the acute stress-field of a dialectical advance of human understanding.

As a firm mathematical foundation for further discussions of Least Action, here is an elegant sequence of steps leading from Newton to Least Action, following closely the argument given by Cornelius Lanczos in his Variational Principles of Mechanics. I have distinguished seven steps in this argument, adding a few notes by way of commentary.

Note that this does not propose to prove the truth of Least Action (though some rugged Newtonians such as Kelvin might take it in this sense!). Rather it demonstrates the formal equivalence of Newton’s laws and the principle of least action. Lanczos points out that the argument is reversible: can be traversed in either direction. The two equations are formally equivalent, but speak of completely different worlds.

We should note that they are not of equal explanatory power. Least Action serves as foundation for General Relativity and Quantum Mechanics, areas in which Newton is powerless.

Organism vs. Mechanism: Science at the Lagrangian Divide

The Lagrangian equations are a powerful set of differential expressions describing the motion of a complex system.  With one equation for each component of the system, they would seem to offer a powerful expression of the relation of part to whole. They are, however, seriously ambivalent: they can be read in either of two opposite ways. They present, then, a stark problem for the art of interpretation, the highest branch of rhetoric, as it comes from Augustine to Bacon and Newton.  The same statement becomes a watershed; it may belong to one world, or its opposite – but not both.  Each is a containing frame, within which we picture, and live, our lives

Read in one way – the way most common today – they are seen as derived from Newton’s laws of motion, and thus adding nothing fundamentally new. From this perspective, they merely rephrase Newton in terms of the concept of energy, a mathematical convenience in certain circumstances but making no fundamental change in our understanding of the natural world. In this interpretation, they express what we today call mechanism, which sees the motion of any system as the mere aggregation of the motions of its individual parts. Causality flows upward; motions of the parts explain the motion of the whole.

Seen from the other side of the Lagrangian watershed, however, the same equations express a world of a totally different sort. Here, the same equations are derived from the Principle of Least Action – a concept which readers may recognize as one of the recurring themes of this website.  The system itself as a whole, described in terms of potential and kinetic energy, becomes the primary reality and the source of the motions of the parts. Causality arises from the  interplay of these energies, and flows in the reverse direction, from whole to part.

Within the world of mechanism – the first interpretation – there is no place for goalor purpose. These are concepts considered far too vague to meet the standard of objectivity, the signature of modern science.

Remarkably, however, Least Action reconciles purpose with quantitative objectivity. By means of the mathematical technique of variation, which considers all possible paths, this principle seeks the optimum path by which potential energy may, over he whole course of any natural motion, be transformed to kinetic. In this interpretation of Lagrange, then, our world-view is transformed. Science itself, while remaining strictly objective and quantitative, becomes at the same time goal-oriented – all at once!

More than this, however, science on the Least Action side of the Lagrangian divide becomes, at last, fundamentally organic. This arises from a further, crucial feature of Least Action: if a system as a whole moves in such a way as to minimize action,so also will, within the bounds of external constraints, every part of that system. The goal which belongs primarily to the whole, is pervasive: it is shared by every part.

It was important in stating this principle to add “within given constraints”, because a rigid part of a man-made machine has few options. By contrast, the myriad components of a leaf, or of a cell or enzyme within the system of a leaf, navigate among unimaginable options toward the common goal of turning sunlight into life, over the season of the leaf, the life of the tree, or the evolution of photosynthesis on earth.

It is this community of purpose, nested and shared, which renders a system trulyorganic – a living being, something fundamentally beyond any bio-molecular mechanism, however intricate.

It is hardly necessary to add that it is this sense of nested purpose and shared membership in natural communities which has been so lacking during the long reign of mechanism. Our so strongly-held worldview has diverted us from that other option, which has nonetheless long formed a strong alternative flow of thought and practice in science, mathematics, politics and the arts. Now in many ways, not least the earth’s biosphere itself, the demand is upon us to recognize that we do have an option of immense importance. Viewing this whole scene now, we might say, from the Lagrangian ridge-line itself, with both worldviews clearly in view, our task is truly dialectical: leaving none of the insights of the past behind, we are in a position to move forward into a new, far richer and wiser world.

That new world-view, which has appeared here as a richer interpretation of Lagrange’s equations, is the ongoing theme of this website – always with an eye to Maxwell’s turn to Lagrange as mathematical vehicle for the launch of his concept of the electromagnetic field, paradigm, if ever there was one, of that whole system of which we have been speaking.

[A brief introcution to the Principle of Least Action is given in my lecture, “The Dialectical Laboratory” .

It is important to add that in this thumbnail sketch, many nuances of the application of Least Action have been left without mention]

"The Dialectical Laboratory": A lecture on behalf of holism in the sciences

My lecture, the “Dialectical Laboratory ” (see the "lectures" section of this website) , was given as a sort of parting statement to the St. John’s College community in Santa Fe.  But though directed to the college, and expressed by way of references to certain of the “great books” of that tradition, its message is of far broader import.  The “dialectical” issue – meaning, a watershed of western thought – is between a science based on mechanical actions between disparate parts, and a holistic science in which wholeness is respected, and whole systems are regarded as fundamental, not as mere aggregations of parts.  

Each of these two very different scientific approaches has its rigorous theory, and either can be used to solve engineering problems.  But conceptually they are worlds apart, and I am convinced it’s crucial that we follow the way of holism, and learn, before it’s too late, to appreciate and work with systems – from the least living organism to the global environment – which are more than the sum of mechanical parts.  Science is moving in this direction, but there is now no time to lose! 

Comments on these remarks, as well as on the lecture itself, will be welcome in reponse to this posting. 

In Praise of Generalized Coordinates

I've been expressing my enthusiasm for a holistic approach to the understanding of nature -- in relation to my favorite topic, the electromagnetic field, this takes the form of the Lagrangian equations for the field as a single, connected system characterized by its energy, not by forces.  It was crucial to Maxwell's development of the equations of the field in his "Treatise on Electricity and Magnetism" that they be formulated as instances of such a connected system -- i.e., in Lagrangian terms, and NOT on the basis of Newton's laws of motion.  (The difference -- very fundamental to our understanding of nature -- is developed in "The Dialectical Laboratory", in my "Lectures" menu.) Now, the question arises: "If we start in this way, from the 'top down', how do we ever arrive at the elements?"   The answer is, "We DON'T!" We move logically "downward" by finding the dependence of the energy of the whole system upon ANY set of measurements we want to make -- provided only that it's a complete (i.e. sufficient to determine the state of the system), with each measure "independent" of the others. We find such a set of measurements by doing experiments -- and when we get them, they are called "generalized coordinates".  The important thing is that there may be many ways we can define them, each set as good as the others: and in the whole process we never get any"real,underlying elements" -- we don't need them!  Reality is founded at the top, not the bottom, of the chain of explanation.   This is Maxwell's new view of physical reality, founded upon the field.  It is the opposite of the notion of "mechanical explanation", and it is the direction which our approach to nature desperately needs to take as we approach the challenges which lie before us today.  In terms of the philosophy of science, Maxwell it seems was far ahead of his time.  I propose to call this the "Maxwellian Revolution". 

Indigenous Views of Nature and the Deep Roots of Western Science

When I wrote yesterday about the "deep roots" of Western science, I intended to point to a possible relation this opens up between the domain of "science" and Indigenous views of the natural world.  If we follow that line of development which leads from Aristotle through Leibniz to the holistic mathematical physics based on the Principle of Least Action, we find ourselves in a position much closer to that of Native American thinkers than we might have expected.Modern science in its mechanical mode cuts off "science" from any sense of wholeness or, especially, of purpose. It wants to reduce all quality to quantity, all motion to the operation of laws which bind matter apart from any sense of goal or meaning, and sees "nature" exclusively as an object from which we stand apart as mere observers. None of these limitations apply to the physics in the holistic mode.  Least Action applies to whole systems, and sees systems moving directionally toward the optimization of a quantity which applies to the system as a whole.  Although this goal may be no more than the optimization of a mathematical quantity, it opens the way to thinking of systems such as organisms or ecologies as moving as wholes toward ends -- a line of thought of which the modern world is in desperate need.One more link in this line of thought: the modern computer is bridging the gap ;between "quantitative" and "qualitative" thinking.  What goes in as number typically comes out on the computer screen as a graphical image readily grasped by the intuitive mind and conducive to interpretation in terms of purposes and goals. We can see how systems are moving, and where they "are going".   Nothing stands in the way of reading these in terms of purposes, and that is what we do on a daily basis -- think for example of evidences of the consequences of global warming emerging from complex computer modeling.  Thinking in this way in terms of whole systems,  understanding their motions in terms of a mathematics of optimization, and bridging the gap between quality and quantity -- all this is yielding an approach to science at once new and old -- in a continuous thread leading from Aristotle into the age of the modern computer.  If we follow that path and think of modern science in terms like these, then it seems to me the gap between a holistic science and Indigenous relations to the natural world is not as deep as it had seemed.  Set aside mechanistic thinking, embrace the sense of nature as a whole of which we ourselves are part, admit goal as a category amenable to science -- and then the old gap between Indigenous, or simply hunan views of the world, and those of "western science", begins to dissolve.   Thus the Cosmic Serpent project, designed to consider this relationship, begins to look much more promising than it otherwise might have.   

The Deep Roots of “Western Science”

I’m very excited to have been invited to participate in the Cosmic Serpent project, which will be exploring the relationships – likenesses and differences – between Indigenous views of Nature, and the world-view of “western science”.

My first thought about this is that what we are accustomed to calling “western science” is not one well-defined, monolithic structure, but rather a growing and changing, organic body including strongly contrasting strands and a deep tap root which reaches far back in history to ancient Greece and beyond.

It is this richness and diversity of our present notion of “science”, together with its vigorous signs of growth, which make the Cosmic Serpent conversation something far more than a confrontation of two distinct ideas. Whether there’s the same degree of diversity and growth within Indigenous approaches to Nature is something I don’t pretend to know, but the coming conversation may reveal.

I feel impelled to say something more about that deep “tap root” of modern science, as it lies close to my heart and has been the subject of much that I’ve thought about and written. (I wrote about one aspect of it in the lecture “The Dialectical Laboratory”, elsewhere on this website.) For me, as we look backwards from our present stance toward a distant past, it is Leibniz who’s the key. Between Leibniz and Newton lay a split far more important than the question of prioty in laying the foundations of the calculus usually referred to. In ways not always recognized, Newton was looking to Christian scripture, especially the Old Testament, when he placed the notion of “law” at the foundation of his Principia. Leibniz, by contrast, was looking to Aristotle and saw intelligible principle – not “?law” – as the basis of our approach to Nature. Two of Leibniz’ crucial terms: energy – potential and actual – come straight from Aristotle’s Physics, and remain to this day beacons of an alternative path in physics. Not forces between particles, the dominant concept of the mechanical view of Nature – but motions of whole systems guided by principles rightly thought of as holistic – set this other course. It becomes formulated mathematically as the law of least action, which evolves in turn into the equations of Lagrange and Hamilton, and in general into the Variational approach to natural motions. It is an approach inherently compatible with the notion of TELOS, or goal. In a broader arena, it is at home, for example, with Gestalt theory in psychology and the theory – at once of art and science – which Goethe sets over against that of Newton in his Farbenlehre, the Theory of Color.

For the practicing physicist, the Newtonian and the Lagrangian methods may seem convenient alternatives to be called upon as occasion demands. But in truth they reach very deep into alternative conceptions of the natural world and its ways. As I explore in Figures of Thought, it was not for convenience but out of deep conviction that Maxwell chose the Lagrangian approach in his own development of the equations of the electromagnetic field in his Treatise on Electricity and Magnetism. That this is an issue for human thought in general, and not a problem whithin mathematical physics alone, is shown beautifully by the fact that Maxwell chose the Lagrangian method as the way to express within mathematics the insights of Michael Faraday, who knew, and wanted to know, no mathamatics.

I have to acknowledge that there’s a manifest contradiction in what I’ve just written: I spoke at the outset of one “tap root” of science, but this whole discussion has been of two: one Newton’s, and the other that of Leibniz. I’m convinced these two lead back, by way of Alexandria, to one lying still deeper – but that must be the subject of another “blog”!