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I'm a Ph.D. student in experimental condensed matter physics. My research mainly uses X-ray and neutron scattering techniques to probe the microscopic dynamics and structure of nano-confined materials. The main project for my doctoral work is a set of neutron scattering studies of liquid helium confined in porous media. A B-movie enthusiast, I'd rather watch Sorority House Vampires from Hell or War of the Robots than the latest blockbuster. So much the worse for me.

About The Blog

This space is allocated for musings about science, life, and society. I am writing mostly as a student and an amateur, so I ask for forgiveness from the real experts who might stumble across this. I hope to learn something by talking with others, or at least occasionally de-pressurize my opinionated soul.

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Why Study Philosophy?

Timmo
Philosophy is an unusually self-conscious academic discipline.  Any observer to the history of philosophy will notice that there are very few points on which there is unanimity among philosophers, that old debates continue on, and that views which disappear for some time are often later revived in new forms.  Controversies are not resolved, but are abandoned due to all kinds of contingent historical factors.  Moreover, philosophical views never enjoy a high level of certainty and always seem open to further questioning.  As a result, philosophers often revisit the questions of what philosophy really is, what it should be, and how philosophers should proceed.  These questions are all the more urgent today because, amid major slashes to university budgets, the survival of many philosophy departments, and perhaps the discipline itself, is in danger.  The case for philosophy needs to be made to ensure its long-term survival.

It is popular in analytic philosophy today to say that philosophy is argumentation or conceptual analysis, and that main duty of philosophers is to produce, analyze, and criticize arguments.  This avoids, perhaps, the embarrassment of rarely arriving at stable consensus.  However, it is hard to think of an academic discipline or intellectual activity that does not require the production, analysis, and criticism of arguments.  It is also not likely that philosophers are especially better at producing arguments than other intellectuals.  Moreover, many of the great  philosophers, like Plato or Hobbes, produced really terrible arguments, and the value of studying Plato or Hobbes does not lie in what can be learned by reproducing their arguments in the form of two-column proofs.

In his book, Problems of Philosophy, Bertrand Russell seriously considered what the value of philosophy might be in light of the concerns raised by people who are "under the influence of science or practical affairs."  One might worry that philosophy consists of nothing more than "innocent but useless trifling, hair-splitting distinctions, and controversies on matters concerning which knowledge is impossible."  Russell, however, sees value in the difficulty and uncertainty of philosophy because "it removes the somewhat arrogant dogmatism of those who have never traveled into the region of liberating doubt..."  Philosophy changes our intellectual temperament by enlarging our conception of what is possible and reducing the stranglehold of our prejudices:
The value of philosophy is, in fact, to be sought largely in its very uncertainty.  The man who has no tincture of philosophy goes through life imprisoned in the prejudices derived from common sense, from the habitual belief of his age or nation, and from convictions which have grown up in his mind.... the world tends to become definite, finite, obvious; common objects rouse no questions and unfamiliar possibilities are contemptuously rejected.  As soon as we begin to philosophize... we find... that even the most everyday things lead to problems to which only very incomplete answers can be given.
Here Russell is a mouthpiece for an old piece of Socratic wisdom.  Socrates asked his fellow Athenians: What is knowledge?  What is justice?  What is friendship?  What is piety?  The people he talked to had confident, but unconsidered, answers to those questions.  Socrates interrogated the beliefs of these people, delving deeper into what they meant, and often found hidden contradictions in their answers to his questions -- Socrates showed people that they did not know everything that they thought they knew.  Sometimes Socrates ventures his own answers to the puzzles he poses, but just as often the Platonic dialogs end inconclusively, leaving the reader to reflect upon what she might say if she were part of the conversation.  The Oracle at Delphi once prophesied that Socrates was the wisest man in Athens, but Socrates said that if he wise it was because he knew that he was ignorant!

Among Socrates' enduring lessons is things which seem obvious may be false, and that there maybe hidden contradictions or puzzles in our beliefs.  We should therefore critically examine things which we take for granted, and this will include our attitudes about ourselves and our society.  In 1944, Wittgenstein wrote a letter to his friend and student Norman Malcolm, recalling a tense dispute they had.  Malcom claimed that it was impossible that there was a British plot to assassinate Hitler because it would be against the national character of the British people.  It is worth quoting the letter at length:
...we had a heated discussion in which you made a remark about 'national character' that shocked me by its primitiveness.  I then thought: what is the use of studying philosophy if all that it does for you is enable you to talk with some plausibility about some abstruse questions of logic, etc. & if it does not improve your thinking about the most important questions of everyday life, if it does not make you more conscientious than any... journalist in the use of the DANGEROUS phrases such people use for their own ends.  You see, I know that it's difficult to think well about 'certainty', 'probability', 'perception', etc.  But it is, if possible, still more difficult to think, or try to think, really honestly about your life & other people's lives.  And the trouble is that thinking about these things is not thrilling, but often downright nasty.  And when it's nasty then it's most important.... You can't think decently if you don't want to hurt yourself.
Here Wittgenstein points out the dangerous naivety of Malcom's ideas about national character.  He reminds us that the effort spent raising and addressing esoteric questions about formal logic and epistemology ought to prepare us to confront the yet harder and more important questions of life.  For example, the law of the excluded middle and the law of non-contradiction are intuitively appealing principles, ones we might readily accept without argument or much reflection.  But, it is possible to give powerful reasons to adopt intuitionist or paraconsistent logics in which these logical laws are not universally valid.  Even plausible or common sense ideas about elementary reasoning might turn out to be mistaken, and Wittgenstein would tell us that this lesson about fallibility and prejudice should spill over to other domains, such as pressing moral and social conflicts.  Russell would have agreed: "The mind which has become accustomed to the freedom and impartiality of philosophic contemplation will preserve something of the same freedom and impartiality in the world of action and emotion."

At the same time Wittgenstein wrote to Malcom, Einstein corresponded with a young professor at the University of Puerto Rico who wanted to incorporate philosophy of science into his teaching of introductory physics.  This is something which is uncommon in physics courses today.  Einstein endorsed the project:
I fully agree with you about the significance and educational value of methodology as well has history and philosophy of science.  So many people today -- and even professional scientists -- seem to me like someone who has seen thousands of trees but has never seen a forest.  A knowledge of the historic and philosophical background  gives that kind of independence from prejudices of his generation from which most scientists are suffering.  This independence created by philosophical insight is -- in my opinion -- the mark of distinction between a mere artisan or specialist and a real seeker after truth.
Einstein, much like Russell, thought that philosophical training cultivates independence of judgement and helps free students from the common prejudices of their times.  He once said that his most capable students, "those who distinguish themselves by their independence of judgement and not just their quick-wittedness," cared deeply about epistemology: "They happily began discussions about the goals and methods of science, and they showed unequivocally, through tenacious defense of their views, that the subject seemed important to them."  In my experience as a graduate student in physics, I have found that many bright and serious scientists light up whenever fundamental questions about science are raised.  Nevertheless, despite Einstein's advice, methodology, history, and philosophy of science are often not part of one's scientific education.

These titans of intellectual history teach us that much of the value of philosophy lies the way its study cultivates independence of judgement, consciousness and suspicion of accepted ideas, the ability to look forthrightly at possibilities which are uncomfortable or unpalatable, and the way its openness undermines the false self-assurance which haunts even our most cherished views.  Nietzsche warns, "A very popular error: having the courage of one's convictions; rather it is a matter of having the courage for an attack on one's convictions."  This piece of Socratic wisdom is the perennial lesson of a philosophical education.  It is a lesson which, as Einstein and Wittgenstein testify, we can bring to other intellectual projects or even urgent moral, social, and existential questions.  Acquiring the intellectual humility, honesty, and courage that is the mark of a truly philosophical cast of mind is what makes philosophy worth studying, and what earns its place in our institutions of higher learning.
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Truth: Scientific and Beyond

Timmo
A theologian friend wrote to me asking, "What sort of truth does science aim to uncover?"  If I have to state what the goal of scientific inquiry is, then all I can say is fairly traditional and rather empty: we want to know what Nature is like and understand how it works.  An individual scientist or group of scientists professionally undertake to expand the scope, precision, and rigor of how we describe natural phenomena and the theories which purport to explain them.  The defining characteristic of modern science is the practice of experimentation.  We make careful observations under known conditions, which are frequently artificial and controlled ones.  Measurements are made with properly calibrated instruments according to techniques that are themselves critically examined.  In the most highly developed sciences, mathematical models are invented that are both qualitatively and quantitatively compared with experimental measurements.  Scientists attempt to tackle all sorts of questions using these methods, whether it is the motion of the planets, the electronic properties of semiconductor transistors, the life cycle of malaria, the acquisition of natural language by human children, the chemical structure of complex polymers, the birth of galaxies, protein folding, the ecology of the very deep ocean, or whatever else you can imagine and think you can tackle.

There's little reason to doubt that the natural sciences and engineering have been and continue to be very successful enterprises.  They have shaped our lives in many direct, practical ways, as well as exert enormous cultural and intellectual influence.  The domain of the sciences is the area where we have the best kind of knowledge available -- what Enlightenment thinkers would have called scientia, the highest and most rigorous kind of knowledge.  But, what we know is actually very little, and really rather narrow.  One lesson that I have drawn from my own scientific training is there is vast obscurity and darkness all around this patch we know about.  One should not get the impression that everything is more or less figured out -- on the contrary, as science advances, we can see an ever widening horizon of ignorance.  The more we learn about Nature, the more we discover how strange it is and how much more there is to the world than meets the eye.  This is a great part of the pleasure and excitement of doing science.

Human affairs, existential concerns, and matters of cosmic importance, remain, now and for the foreseeable future, at the horizon of our understanding.  Scientific inquiry can tell us a lot about ourselves because we can make ourselves the object of study.  Psychology, medicine, and social studies do precisely this.  But, I don't see how we can deduce from experimental data what is the good life, what kind of society is just and decent, how to live a life of virtue and love and decency, whether God is at work in the world, whether we or the universe has a purpose, and so on.  It is worth quoting Bertrand Russell at length:

Almost all the questions of most interest to speculative minds are such as science cannot answer...  Is man what he seems to the astronomer, a tiny lump of impure carbon and water impotently crawling on a small and unimportant planet?  Or is he what he appears to Hamlet?  Is he perhaps both at once?  Is there a way of living that is noble and another that is base, or are all ways of living merely futile?  Must the good be eternal in order to deserve to be valued, or is it worth seeking even if the universe is inexorably moving toward death?  Is there such a thing as wisdom, or is what seems such merely the ultimate refinement of folly?  To such questions no answer can be found in the laboratory... Science tells us what we can know, but what we can know is very little, and if we forget how much we cannot know we become insensitive to many things of very great importance.

Scientific inquiry, in its modern incarnation, can assist and inform the way we think about ourselves and the world.  Surely, a responsible person takes seriously the need to include what the vistas of science disclose.  But, so far as I can tell, it does not remove the need for philosophical and spiritual reflection on how we should live or who we ought to become.
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What Marx Can Teach Us Today

Timmo
The libertarian political commentator Will Wilkinson recently tussled over the web with philosopher Brian Leiter over whether we ought to think of Marxism as "realistic."  A friend asked me to weigh in on their discussion, and this is rather difficult to do given the both the venom of their exchange and the way each was focused on discrediting opponents rather than developing any ideas.  It was fairly ugly, and there's nothing of a philosophical spirit or moral presence in what either writer had to say.  Wilkinson is puzzled that Leiter "an erudite guy with an evidently robust bullshit detector" could "treat old-school Marxism as a plausible explanatory theory," and dismisses his "disastrously stupid idea" as "inconsistent with the sort of social order that does meet human needs reliably and well."  With equal contempt, Leiter writes that Wilkinson is a cry-baby and tells us that "the simple fact is that I don't respect his intelligence."  Leiter seems to believe that Wilkinson should not be taken seriously because his "ideological blinders" prevent him from seeing what is "obvious to anyone."  One thing that gets lost in the discussion is who Marx was and why his thinking might be relevant to us today.

Wilkinson rehearses a standard view that the experience of the 20th century shows that Marx's political philosophy and economics is deeply wrong, and dangerously so.  He writes, "Make no mistake, Marxists did lose a big argument, one we now know as 'the 20th century'" and reminds us of "the tendency of Marxism when applied to produce totalitarian dictatorships that have caused upward of 100 million deaths."  For many people, the tyranny of the Soviet Union, China, Cuba, and other communist countries clearly reveals that Marxist politics is authoritarian; the collapse of the Soviet Union in the early 90's shows that communist economies are not, at least in the in the long run, viable.  Marxist political parties have largely evaporated and do not play a significant role in politics.  Today, we often hear that communism looks good on paper but never works in practice: people who take Marx seriously are not "realistic."

Whenever anybody says something very confidently, we should stop and ask ourselves: 'Wait a minute, is that true?'  Is it really true that after the 20th century we should discard Marx?  Was Marx an advocate of totalitarianism and a proponent of an nonviable economic system?  As a university student in 1840's Germany, Marx was a lover of Enlightenment classical liberalism and became swept up in the upheavals and struggles for social change that were happening then.  The French Revolution and the revolutions of 1848 had promised liberty, equality, and brotherhood, ideals to which Marx adhered.  But, Marx saw that the emerging capitalist system did not deliver on those promises, and brought widespread misery as well as inequality of wealth and power.  Marx devoted his life to understanding why liberal capitalism never delivered on its promises of liberty, equality, and brotherhood.

So, Marx undertook a detailed empirical, historical, and economic analysis of 19th century capitalism.  He wanted to understand how social change takes place so that it might be possible for future movements to bring about a society that has liberty, equality, and brotherhood.  Marx was focused on this, writing very little about what a future communist society might look like, how its economy would operate, or how it would solve the problems that it would encounter.  Cautious about the what the future might hold, Marx did not approve of what he called crystal-ball gazing -- he wrote about the 19th century society in which he lived and the historical currents he detected, or thought he detected, at work.  In particular, he never prescribed a state-run command economy as an ideal to rival capitalism.  It is worth quoting economists Resnick and Wolff at length:
Marx believed that he had found an important flaw in the way revolutionaries understood European society.  That flaw concerned their underestimation of the significance of economics in shaping societies and their histories.  More precisely, the revolutionaries of 1848 had neglected the role of class, by which Marx mean the production and distribution of surplus labor within the economy.  This neglect blinded them to the class aspects of European society, and that blindness weakened their analyses of capitalism and contributed to the failure of their revolutionary projects.
Next to the Holy Scriptures, Marx's writing must be the most dishonestly and dogmatically read material, both by its detractors and by its 'friends.'  His personal motto was Question Everything, and his writing are full of empirical findings, historical material, painstaking analysis, and detailed argumentation.  He said that the vice he hated most was servility.  However, already in the late 1870's there were fanatics who dogmatically adhered to Marx's ideas, people who called themselves Marxists.  About those people Marx said: "All I know is that I am not a Marxist."  I think we can be confident that Marx would have had a similar attitude toward Lenin, Stalin, and communist commissars generally.  The philosopher Allen Wood writes, "To read him in a dogmatic spirit, as if his writings were some sort of holy writ, is to miss what is best about him: the terrifying openness of mind represented by his own way of thinking and by the intellectual position into which he forces his readers -- especially those who remain unconverted by this theories."  Marx has very little to do with either the temperament or the political programs of many so-called Marxists.

One of Marx's lasting contributions to political economy was his class theory, where 'class' is his technical term for how we organize the production, appropriation, and distribution of the goods and services our enterprises produce.  In our society, most people work within firms called corporations.  In a corporation, all power is held in the hands of a board of directors, and they make all of the majors decisions about what is produced, where it is produced, how it is produced, how the enterprise is managed and run, what will be done with the profits, what will be done with investments, and so on.  Workers are permitted to rent themselves to corporations, following the orders that come from the Board of Directors through a managerial chain.  The workers have little or no say over what happens to the fruits of the labor -- and this is what Marx calls class exploitation, a kind of systematic social theft.

Working in such a hierarchical system produces, as Marx saw, deep feelings of alienation toward one's creative, productive life.  In capitalism, the workplace is not a place of self-realization or meaningful service toward others.  Instead, one must submit to the orders of masters who control the capital, people thereby make the major decisions as to how life goes on in society.  As a champion of freedom, Marx did not want people crammed into such a servile life, and was troubled by the nature and consequences of capitalist class structure.  As Resnick and Wolff observe, "class exploitation occurs in our society and [our political system], literature, family structure, sports, television programming, religions, and incomes are all complexly shaped by such exploitation."  What the revolutionaries of the 19th century did not understand is that their achievements would be undermined by authoritarian control on the job.  Marx is relevant to us today because he would urge us to make the workplace a site of social change: we should bring democracy to the workplace.  (It is worth mentioning that Noam Chomsky persuasively argues that Lenin was against the core idea of socialism, namely worker control over production, here and here.)

The advocates of capitalism claim that it is an efficient, free, and rational economic system.  But, if our eyes are open to the troubling ways that that class exploitation shapes our lives and our society, then we are likely to say that capitalism looks good on paper, but doesn't work in practice.  We should ask ourselves whether it is really true that there is no alternative to capitalism, and, like Marx, question everything.

01/23/12: Some minor typos corrected.
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God and the Boulder He Can't Lift

Timmo
There is a popular puzzle about God's omnipotence: can God create a boulder so heavy he can not lift it?  If God can create such a rock, then there is a rock that He cannot lift.  In that case, he cannot be omnipotent.  On the other hand, if God cannot create such a rock, then there is something God cannot do.  In that case, He is surely not all-powerful.  It looks like the notion of omnipotence is self-contradictory.

The usual response to this puzzle is that the answer to the question is "no," but this is not a restriction on God's power.  The reason is that the question stipulates that God do something logically impossible, and it is impossible for God to do something logically impossible.  But, it is not a "real" limitation on the power of God if He cannot do something logically impossible.

It is worth dwelling on this puzzle because the answer to the question might prove to be 'yes' on closer examination.  The modal logic S5 is often taken to formalize the notions of logical necessity and logical possibility.  One way to look for a genuine contradiction is to attempt to formulate the puzzle in S5.

There is supposed to be a contradiction between the following propositions:

(1) God can lift any boulder. [For all x, if x is a boulder, then, God can lift x.]
(2) It is possible that there exists a boulder that God cannot lift. [Possibly, there is an y such that y is a boulder and God can not lift y.]

If we let g be a constant which rigidly designates God, then (2) and (3) are written:

(1')  (∀x)(Bx  ⊃ ◊gLx)
(2')  ◊(∃x)(Bx & ~◊gLx).

Consider quantified S5 with an expanding domain.  It can be shown that (1') and (2') are mutually consistent in S5 by producing a model M for S5 in which both (1') and (2') are true at some world w.

Recall that a model M for quantified S5 is a quintuple <W, R, D, E, V>, where: W is a non-empty set of possible worlds; R is the binary accessibility relation on W; D is a non-empty domain of objects; E is a function E: W →  P(D) mapping each world w to the objects which exist at w; and V assigns extensions to the predicate letters at every world.  R is an equivalence relation.  For each n-ary predicate Pn, V(Pn, w) ⊆ En(w) -- that is, at each world w, the extension of an n-place predicates are sets of n-tuples of objects existing at w.  When evaluating a quantified formula at a world w, the quantifiers are understood range only over objects which exist at w.  The idea of this semantics is that different objects exist at different worlds and quantifiers range over things which exist.

Consider the following model M: W = {w, w*}, R = {<w, w>, <w, w*>,  <w*, w>,  <w*, w*>}, D = {g, b}, E = {<w, {g}>, <w*, {g, b}>}, V(B, w) = V(L, w) = V(L, w*) = ∅, V(B, w*) = {b}.  Intuitively, there are two worlds w and w* such that they each see themselves and each other.  At w, the only object which exists is God and there are no boulders and nothing lifts anything.  At w*, both God and Boulder exist, Boulder is a boulder, and God does not lift Boulder.  The model M can be represented as a cartoon:


In the model M, both (1') and (2') are true at w.  Since there are no boulders at w, (1') is automatically true (due to the "vacuous conditional").  (2') is true at w if w can see a world in which a boulder exists that God cannot lift.  w sees w*.  Is (∃x)(Bx & ~◊gLx) true at w*?  In w*, Boulder is a boulder.  Is ~◊gLb true at w*?  The answer is yes because every world that w* sees is a world in which gLb false.  Therefore both  (∀x)(Bx  ⊃ ◊gLx) and ◊(∃x)(Bx & ~◊gLx) are true at w.  It follows that (1') and (2') are mutually consistent in quantified S5 with expanding domains.

Logically speaking, God can create a rock so heavy that he can not lift it.
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The Birth of Science and the Driving Force of Capitalist Development

Timmo
The Scientific Revolution brought about profound and lasting changes in not only our ideas about what Nature is like, but also how inquiry into Nature's workings should proceed.  Medieval scholastic thinkers working before the Scientific Revolution pursued questions about Nature primarily by either deferring to ancient authorities or by philosophical argumentation.  Students in European medieval universities learned the art of disputation.  A professor would select a thesis for one pupil to defend and another to attack, and each would have to argue according a canon of strict logical rules and metaphysical principles.  Francis Bacon explained that the Scholastic approach to learning about Nature rested on "anticipations of the mind."

Bacon was critical of Scholastic learning, frustrated that their achievements "stand like statues, worshiped and celebrated, but not moved or advanced."  He insisted that Scholastic methods are inadequate if we want "to overcome, not an adversary in argument, but nature in action."  To go beyond making "petty and probable conjectures" that merely stem from "anticipations of the mind," we should carry out an "interpretation of nature."  Breaking with their medieval predecessors, scientific revolutionaries like Boyle, Galileo, Gilbert, Tycho Brahe, and many others, cultivated the practice of careful observation and experimentation.  In an experiment, one prepares controlled conditions and makes measurements with well-calibrated instruments.  Mathematical models are introduced that are intended to explain what is observed in experiments, and are tested against further experiments.  This approach is the hallmark of modern scientific inquiry, so much so that the physicist Feynman once pronounced that "the fundamental principle of science, the definition almost, is this: the sole test of the validity of any idea is experiment."

The adoption of "experimental philosophy" during the Scientific Revolution was a profound and fruitful transformation of human inquiry.  The roots of the Scientific Revolution raise an interesting historical puzzle: Why did the Scientific Revolution take place in Europe, and why did it take place at the time that it did?  In particular, what made it possible to abandon the Scholastic approach and adopt experimental philosophy?  On the face of it, Europe looked like the least likely place to undergo an explosive growth of scientific knowledge given its relative cultural backwardness at that time.  There was a wealth of knowledge and rich intellectual traditions in China and the Islamic world, and yet modern science originated in Europe.

One possible explanation is that the Scientific Revolution was fortuitous.  There is no way to predict in advance the development of human ideas, especially major breakthroughs.  It happened that, at this moment in Europe, there was a flowering of luminaries who reconsidered not only the principles of the Scholastics' metaphysics, but also their methodology of disputation.  This suggestion, however, fails to take into account that the heroes of the Scientific Revolution were part of a broader intellectual climate in Europe that was being shaped by radical changes in European society.  The dissolution of the old feudal order and the weakening of ecclesiastical authorities opened up new avenues of inquiry, and this social upheaval made the Scientific Revolution possible in Europe and not in China or the Islamic world.

In his book, A People's History of Science, Clifford Conner documents the way in which the scientific revolutionaries were inspired by the empirical and mathematical methods used by artisans in their workshops.  Clifford notes, "The writings of Galileo, Bacon, and Gilbert themselves all clearly reveal that their inspiration came from miners, sailors, blacksmiths, foundry-men, mechanics, lens-grinders, glassblowers, clockmakers, and shipwrights -- the manual workers of that era."  Bacon, in particular, proposed that an extensive encyclopedia of craft knowledge be compiled, giving inquirers into Nature a extensive data set to draw from.  The mathematization of scientific inquiry was proceeded by the calculating methods of merchants.  Students interested in practical mathematics "usually did not go to the university, but sought out a reckoning master, a man skilled in the arts of commercial computation, with whom to study."

If the scientific revolutionaries were inspired by the methodology of "manual workers of the era," then what brought this to their attention?  The work of merchants and manufacturers came to their attention because of the growing presence of markets and capitalist enterprises, which were displacing the old feudal economic system at that time.  Conner explains:
...the rise of capitalism created the social preconditions for a scientific revolution.  A vast increase in the markets for manufactured goods stimulated the inventiveness of artisans and promoted empirical methods of gaining knowledge of nature.  The profit motive spurred competing merchant-manufacturers to seek labor-saving technical innovations, which required knowledge that would provide increased mastery over natural proccesess. 
...The success of the artisans in creating new and useful knowledge of nature inspired a few perceptive scholars to break with their innovation-stifling traditions and formulate new ways of perceiving the world.  Thus were born the "mechanical philosophy," the "experimental philosophy," and the Scientific Revolution.
This warrants a closer examination because it exhibits what the Marxian economist Paul Sweezy called the "driving force of capitalist development," namely the accumulation of capital.  Capitalist enterprises are engaged in competition with each other on the market.  Because each capitalist enterprise needs to secure the conditions of their survival against the impinging threats of their competitors, they have an incentive to accumulate new capital.  As Marx explains, the accumulation of capital is a necessity for each industrial capitalist:
...the development of capitalist production makes it constantly necessary to keep increasingly the amount of capital laid out in a given industrial undertaking, and competition makes the immanent laws of capitalist production to be felt by each individual capitalist as external coercive laws.  It compels him to keep constantly extending his capital, in order to preserve it, but extend it he cannot except by means of progressive accumulation.
Marx proclaims this as an imperative "Accumulate, accumulate!  That is Moses and the prophets!"  Industrial capitalists seek to expand by using their revenue to purchase new raw materials, tools, machines that will later on permit them to accrue even more revenue -- better yet, each industrial capitalist would prefer to have higher quality raw materials and technically more advanced tools and machines.  This makes scientific discovery and technological innovation a high priority in capitalist economies. Marx details how these developments aid in the accumulation of capital:
Every advance in Chemistry not only multiplies the number of useful materials and the useful applications of those already known, thus extending with the growth of capital its sphere of investment.  It teaches at the same time how to throw the excrement of the processes of production and consumption back again into the circle of the processes of reproduction, and thus, without any previous outlay of capital, creates new matter for capital... science and technology give capital a power of expansion independent of the given magnitude actually functioning.
Sweezy sums this up when he writes, "The greatest amount of surplus value and hence also the greatest power to accumulate to the capitalist who employs the most advanced and efficient technical methods; consequently the striving for improvements in universal."  This is the key to understanding why capitalism was able to achieve what feudalism could not: "experimental philosophy" took over and the successful methods of the "manual workers of the era," developing an empirical approach to learning about Nature that provided manufacturers with ever more technologically sophisticated means of production.   Far from a chance innovation in human thinking, the displacement of "anticipations of the mind" by the "interpretation of nature" was occasioned by thoroughgoing change in the economic basis of European civilization.

Marx understood that capitalism "develops continually with the uninterrupted advance of science and technology," and this comes out in the way that the Scientific Revolution and early European capitalism both shaped and made the other possible.
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Magnetism: Natural Enemy of Superconductivity?

Timmo
A century ago, the Kamerlingh Onnes was the first to observe superconductivity in solid mercury at 4.2 K.  Since then, the study of superconductivity has grown into a major enterprise in condensed matter physics.  Several years go, a new category of high temperature superconductors was discovered that incorporates iron into its crystal structure, the "iron-based superconductors."  The compound LaOFeAs undergoes a transition to a superconducting state at 26 K.  The crystal structure sandwiches an FeAS layer in between LaO layers.  The F doping provides the conduction electrons, which propagate in the FeAs layer.  Other compounds like LaOFeAs have since been discovered, but it has been found that if the Fe is substituted for some other element, the superconductivity is lost.  Apparently, the Fe atoms play an essential role in the formation of the superconducting state.

The existence of iron-based superconductors is something of a surprise in light of the finite magnetic moment of iron atoms.  The superconducting state of conventional superconductors, like mercury, is destroyed by the presence of magnetism.  In Type I superconductors, external magnetic fields are expelled from the bulk of the superconductor in what is known as the Meissner Effect.  However, when the impinging external field grows beyond some critical strength, the superconducting state is lost altogether.  In Type II superconductors, external fields are expelled below a critical field H1 , above which the external field penetrates the superconductor in a set vorticies carrying quantized magnetic flux. (In low temperature superconductors, these vortex lines form a static lattice; but, in high temperature superconductors, it is possible for the magnetic vortices to be mobile, forming a "fluid.") The superconducting state is locally destroyed where the flux lines penetrate the material. Above a higher critical magnetic field H2, the superconducting state is lost altogether.

The addition of impurities suppresses the superconducting transition temperature, but after about the addition of 1% of the impurity, the transition temperature is not strongly effected.  On the other hand, magnetic impurities of a few percent typically prevent the superconducting transition altogether!  Metals like iron do not become superconductors.  Taken together, these facts suggest that magnetism is an "enemy" of superconductivity.

This makes good sense in light of the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity, which gives a microscopic description of conventional superconductors.  On this theory, there is an effective, attractive interaction between conduction electrons.  Because there is electrostatic attraction between the lattice ions and conduction electrons, the lattice can be distorted or set into vibration by the electrons.  In field-theoretic terms, conduction electrons interact with each other by the exchange of virtual phonons, the quanta of lattice vibrations.  (Technically, the BCS Hamiltonian contains a term for a shielded Coulomb interaction between the electrons and electron-phonon interactions).  Below a critical temperature, electrons form 'Cooper pairs,' which are bound pairs of electrons with opposite momenta and spin (they are bound, s-wave spin singlets).  The formation of Cooper pairs has a dramatic effect on the elementary excitation.  An energy gap opens up in the spectrum of elementary excitations.  Because of this energy gap, the flowing electrons become a superfluid.  In liquid helium, the velocity of superflow is typically limited by the formation of quantized vorticies; in a superconductor, electrical currents are limited by the formation of magnetic flux vorticies.

According to BCS theory, then, superconductivity is destroyed whenever it is no longer energetically favorable for electrons to form Cooper pairs -- That is, the superconducting state is lost if the difference in energy between spin up and and spin states at the Fermi surface exceeds the Cooper pair binding energy.  Because electrons can couple to magnetic fields through their spin, there is a finite probability amplitude for a spin flip when an electron 'scatters' from an external magnetic field or magnetic impurity.

Since external magnetic fields or contamination by magnetic impurities disrupt the basic mechanism behind conventional superconductors, namely the formation of Cooper pairs, it looks like that magnetism is an 'enemy' of superconductivity.  In that sense, the existence of superconductors in which iron appears to play a crucial role in the superconducting state is a surprise.  It testifies to the inadequacy of the BCS theory to describe superconductivity in general, however great and total its success in elucidating the nature of conventional superconductors.

While no successful microscopic theory has yet been developed to explain high-temperature superconductors, including iron-based ones, it is widely believed that Cooper pairing is still operative.  These Cooper pairs must have a different wavefunction than conventional Cooper pairs -- that is, it cannot be an s-wave spin singlet. In Sr2RuO4, there is evidence from Josephson junction measurements that Cooper pairs form p-waves (l = 1) and have the S = 1 spin-triplet state. And in the cuprates, Cooper pairs have d-waves (l = 2) as the spatial part of their joint wavefuntion, and are in the spin-singlet state.  In order to explain the formation of these more exotic Cooper pairs in YBCO compounds, some theorists have argued that Cooper pairs are bound by the exchange of virtual magnons, the quanta of spin waves.  One would therefore expect that Cooper pairs in iron-based superconductors have more exotic wavefunctions than in the BCS case, and that the binding mechanism that produces them probably involves the magnetic moment of iron in some crucial, but as yet obscure, way.  Much theoretical and experimental work remains to be done to understand these complicated systems.

Perhaps instead of being a universal enemy of superconductivity, magnetism is sometimes deeply intertwined with it.
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Isaac Newton and Intelligent Design

Timmo
Isaac Newton was something of a theologian, and drafted A Short Schem of the True Religion.  He argues against atheism on grounds that would today be called 'Intelligent Design':
Atheism is so senseless & odious to mankind that it never had many professors... Whence is it that the eyes of all sorts of living creatures are transparent to the very bottom & the only transparent members in the body, having on the outside an hard transparent skin, & within transparent juyces with a crystalline Lens in the middle & a pupil before the Lens all of them so truly shaped & fitted for vision, that no Artist can mend them? Did blind chance know that there was light & what was its refraction & fit the eys of all creatures after the most curious manner to make use of it? These & such like considerations always have & ever will prevail with man kind to believe that there is a being who made all things & has all things in his power & who is therfore to be feared.  [my emphasis]
Of course, Newton was working before the advent of the Theory of Evolution.  At the time Newton was writing, there was no plausible natural mechanism that could produce eyes "after the most curious manner" and make use of the refraction of light.
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