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| Albrecht Durer, St. Michael Fighting the Dragon from Wikimedia Commons |
“There is a fundamental difference between religion, which is based on authority, and science, which is based on observation and reason. Science will win because it works.” [emphasis added] Stephen Hawking. ABC Interview, 2010"
The arrogance of scientists is evident nowhere more than in their zealotry against religion." Rabbi Yonason Goldson, Jewish World Review, 26th April, 2017.
"If we discuss a war between science and the Church (notice the difference in upper case), we must define what weapons are legitimate and where the battle is to take place." Robert Kurland,"Truth Cannot Contradict Truth"
INTRODUCTION
This is to be the first in a series of posts about the supposed war between science--let me change that to "scientism"--and Catholic teaching. I'll start off with some historical case studies to show how science has proceeded as a fallible human undertaking. These case studies will then be set in the context of Imre Lakatos's "Scientific Research Programme" to show how science works, its strengths and limitations. Later posts will examine the arguments of evangelists for scientism and (I hope) rebut them. But let's preface all that with a biographical note.
Reading about the recent "March for Science" and what it really stood for*, I thought about my own past skirmishes between belief in science as the all-in-all and my need for a deeper faith. I recalled that time 22 years ago when I told scientific colleagues--friends--about my conversion and Easter entry into the Catholic Church, and I imagined them shaking their heads and saying "What's happened to old Bob, has he gone completely off his rocker?" Those were the sort of comments I had heard 40 years earlier after a promising graduate student in theoretical chemistry became a Evangelical Christian and forsook his career.
Reading about the recent "March for Science" and what it really stood for*, I thought about my own past skirmishes between belief in science as the all-in-all and my need for a deeper faith. I recalled that time 22 years ago when I told scientific colleagues--friends--about my conversion and Easter entry into the Catholic Church, and I imagined them shaking their heads and saying "What's happened to old Bob, has he gone completely off his rocker?" Those were the sort of comments I had heard 40 years earlier after a promising graduate student in theoretical chemistry became a Evangelical Christian and forsook his career.
My friends were tolerant of my idiosyncratic behavior (to my face), but I could imagine them saying "he's not doing science any more so I guess this religion bit is an old age pastime." Or maybe not. According to them, belief in God indicated poor judgment, but not a moral defect. It showed poor taste, like choosing Gershwin over Bach, a Buick over an Audi, or voting for Bush (41) instead of Clinton.
The toleration they showed is becoming is much less common nowadays. There have have been a spate of recent books by theoretical physicists**, evangelical atheists who would convert religious believers to their own faith, scientism. What is scientism? It's the belief that science can explain everything that needs to be explained and that it can provide a foundation for morals and ethics.
That faith in science is misplaced. As my favorite authority on the limits of science, Fr. Stanley Jaki, would put it:
"To answer the question 'To be or not to be?' we cannot turn to a science textbook."
--Fr. Stanley Jaki, The Limits of a Limitless Science.
HOW SCIENCE WORKS--SOME CASE STUDIES
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| Frankenstein's Laboratory, from Wikimedia Commons |
My wife, a student of medieval history, has told me that "History tells you most of what you need to know about a subject", so we'll start with some examples from the history of science to show 1) that science is fallible and tentative, and 2) that it is totally dependent on empirical tests.
The Caloric Theory of Heat Refuted Experimentally
What is heat? Nowadays we usually think of heat as a form of energy, but back in the 18th and early part of the 19th century that was not so. At first it was thought that heat and combustion were inter-related via a hypothetical substance, phlogiston, but this theory was disproved by Lavoisier in the late 18th century by his experiments on oxygen and combustion.
He then introduced a theory in which heat consisted of an invisible fluid, caloric, which flowed from a hot thing to a cold thing. The theory accounted quantitatively for temperature changes when a hot body was put into a contact with a cold one (e.g. dropping a given amount of cold water into a given amount of hot water.) A principle employed in such calculations was that since caloric was a substance, i.e. something material, the total amount of caloric involved in heat transfer had to be conserved.
He then introduced a theory in which heat consisted of an invisible fluid, caloric, which flowed from a hot thing to a cold thing. The theory accounted quantitatively for temperature changes when a hot body was put into a contact with a cold one (e.g. dropping a given amount of cold water into a given amount of hot water.) A principle employed in such calculations was that since caloric was a substance, i.e. something material, the total amount of caloric involved in heat transfer had to be conserved.
In 1798 Benjamin Thompson, Count Rumford, submitted a paper to the Royal Society about his experiments in which boring a cannon could make water boil, and boring with a blunt instrument produced more heat than with a sharp one (more friction with the blunt). The experiments showed that repeated boring on the same cannon continued to produce heat, so clearly heat was not conserved. This experiment validated another theory of heat, the kinetic theory, in which heat was due to the random motion of atoms and molecules.
However the kinetic theory, despite Rumford's groundbreaking experiment, still did not hold sway until some time after James Joule showed in 1845 that work could be quantitatively converted into heat.
James Joule: Work--->Heat
A diagram of Joule's apparatus is shown on the right:
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| Sir James Joule's Apparatus from Wikimedia Commons |
As the weight falls, the potential energy of the weight is converted into work done (a paddle stirs the water in the container against a frictional force due to water viscosity). The temperature rise corresponding to a given fall of weights (work done) yields the amount of heat rise (in calories) of the known mass of water. Since the temperature rise is very small, the measurements have to be very accurate.
It took 30 to 50 years after Joule's definitive experiment (and subsequent refinements and repetitions) for the kinetic theory of heat--heat caused by random, irregular motion of atoms and molecules--to be fully accepted by the scientific community. James Clerk Maxwell published in 1871 a paper, "Theory of Heat". This comprehensive treatise and advances in thermodynamics convinced scientists finally to accept that heat was a form of energy related to the kinetic energy of the atoms and molecules in a substance.
Giving Birth to the Kurland-McGarvey Equation
I want also to illustrate how science works with an example from my own scientific career. So as not to blow my own horn (too much!), I'm going to try to show not only where I succeeded, but where I erred. A few years into my first academic position at Carnegie Tech (now Carnegie-Mellon University) a graduate student in my research group was facing a road block with his research problem. A well-established theory was not giving results matching his data.
After a lot of thought, it appeared that we were not taking into account higher energy levels of the compound (potassium ferricyanide) he was studying. Searching the library, I found a publication by Schwinger and Karplus (recalling my earlier graduate course in quantum mechanics) that offered a road to a solution. After several weeks of intensive devotion, I wrote a paper that incorporated density matrix techniques to account for contributions of all electronic levels and submitted it for a publication. One reviewer pointed out a serious deficiency--I had neglected to account for mixing of excited states with ground state. I acknowledged he was right, asked him to co-author the paper with me and we collaboratively worked it up for publication.
There is an equation stemming from that work, (Google "Kurland-McGarvey Equation") that is widely enough used in the specialty that it doesn't need footnoting for reference. So, one more small brick in the scientific edifice.
Now, the point of all this is to show that science proceeds by correcting errors in theories, errors in which theories--which are meant to be descriptive, not prescriptive--don't fit experimental data. The refereeing process fifty years ago was one where authors were usually willing to be criticized and the reviewers of papers almost always tried to insure that the science in a published paper was good.
Other Experimental Tests of Significant Theories
There are many more examples of theories that were confirmed--i.e. not falsified--by empirical results. Links are given below to some examples of such experimental tests in various fields of science.
Each of these examples above can be rationalized in terms of Imre Lakatos' "Scientific Research Programme", which is discussed below.
Lakatos's "Scientific Research Programme"
The "Scientific Research Programme" devised by Imre Lakatos can be thought of as a sphere: there is an inner core of fundamental principles--not theories, but principles to which theories have to adhere; these principles are assumed, because they seem obvious and confirmed generally by our experience. But, as we'll see below, there are occasions when these fundamental principles are modified or violated. Surrounding this core of fundamental principles is a shell of fundamental or primary theories (e.g. thermodynamics, general relativity, quantum mechanics). Surrounding this shell of fundamental theories are other shells representing auxiliary theories derived from the primary theories and other auxiliary theories. MRI, chemical bonding, heat transfer are examples of such auxiliary theories. And finally there is an outer shell of experimental facts or data. The interplay between the shells and core that shows how science works is illustrated below.
- Lakatos "Scientific Research Programme
In this diagram the inner core principles are linked to fundamental and auxiliary theories, as shown by the black arrows. There is feedback from data to theories, as shown by the red arrows. There is even feedback from data and fundamental theories to inner core principles, as shown by the red arrows.
Examples: Rumford, Joule
The core principle involved in the caloric theory of heat was the conservation of caloric (since it was a substance). Count Rumford's cannon-boring experiments showed that the more the cannon was bored, the more heat was produced; therefore the supply of heat in the cannon was inexhaustible and clearly not conserved.
A core principle involved in Joule's experiment is the First Law of Thermodynamics: conservation of energy, with heat and work as forms of energy. Note that this conservation principle is linked to a fundamental theory of thermodynamics developed in the middle of the 19th century and to theories of classical mechanics developed in the 18th century and early 19th century.
Examples: Einstein's Relativity theories
Einstein's two theories of relativity are striking examples of how theory influences fundamental principle (the red arrow), or perhaps more accurately, how fundamental principles are proposed as a basis for general theories. His theory, special relativity, introduced the following new general principles:
- the laws of physics are the same for systems ("frames of reference") moving at constant velocity (i.e. "inertial systems");
- the speed of light (in vacuum) is constant, regardless of the speed of source or receiver;
- neither energy nor mass is conserved but only mass + energy (from E=mc²)
His general relativity theory introduced the "equivalence principle", that inertial and gravitational mass are the same. In every-day terms, this principle says that a person (mass m) in an elevator accelerating upward experiences a force holding him to the floor due to earth's gravitation, mg, plus a force due to the acceleration of the elevator, ma. This is the same force that the person would experience on a planet where the gravitational acceleration would correspond to g+a, or in a spaceship accelerating at a rate g+a
Example: The Ultra-violet Catastrophe and Quantum Theory
At the end of the 19th century classical physics came across a real stumbling block. Theory predicted that the energy of a "black body" (a body radiating energy, in thermal equilibrium with its surroundings) should go to infinity as the wavelength of the radiated energy approached zero (toward the ultra-violet end of the electromagnetic spectrum).
Planck resolved this problem by positing that energy was not transferred continuously, but only in a small discrete packet which he called a quantum of energy. (And thus was born quantum mechanics.) So this is another example of how data, experiments affect fundamental principles.
Example: Parity Conserved? Right- and Left-handed Symmetry
Parity refers to mirror symmetry. For example, many organic molecules are
- Chiral Amino Acids--Right and Left-handed
from Wikimedia Commons
either right- or left-handed (see the illustration at right of two amino acids, constituents of proteins: COOH is the organic acid group, NH2 is an amino group, C is the central carbon, R represents a general group attached to the carbon). Now biological molecules can be chiral either as a whole, or with respect to the constituent parts. For example, amino acids found in nature are left-handed; sugars found in nature are right-handed; DNA as a whole has a right-handed spiral (helix). The question of why only one kind of handedness for biological molecules came about has fascinated chemists and biologists since the time of Pasteur 150 years ago. There are recent theories to explain this, but they are to some extent conjectural.
Conservation of parity (handedness) had been a fundamental principle of physics until the late 1950's, when a proposal to test it for nuclear weak force interactions--e,g, beta decay of Co-60 nuclei--showed that it was violated. (See here for an expanded story.) Since that time a conservation principle, CPT symmetry, linking parity (P) with charge (C) and time reversal (T) has been found to hold.
Summary
In all the examples described above there is an interaction between theory and experimental data: either the data confirms the predictions of theory or the data requires a theory to be modified or discarded. These interactions are nicely summarized by the Lakatos model, "The Scientific Research Programme".
WHAT SCIENCE CAN'T DO
How do we go from “how science works” to “what science can’t do”? The most comprehensive scheme and, to my mind, the one that best matches actual scientific practice is that of Imre Lakatos, described above. Note again these elements of the scheme: a network of hypotheses AND experimental data. The combination of theory and data requires that predictions or explanations made by models and theory must be validated empirically, if the theory or model is to be truly part of science. Measurements must be replicable, which is to say that essentially the same results are required, for whichever team does the measurement or performs the experiment.
Fr. Stanley Jaki has put more stringent requirements on science:
"Science...is synonymous with measurements, which are accurate because they can be expressed in numbers. Those numbers relate to tangible or material things, or rather to their spatial extensions or correlations with one another in a given moment or as time goes on.” "The Limits of a Limitless Science," Asbury Theological Journal 54 (1999), p.24
This need for numerical assessment strikes out disciplines which most people would regard as science—biology, geology, paleontology, and such. Here I would have to disagree with Fr. Jaki: abduction and retroduction can be used to assess non-numerical data rigorously. A fine example is the development of the tectonic plate theory. It started in 1915 with the continental drift hypothesis of Alfred Wegener, based on the matching coastline shapes of western Africa and Eastern South America, and the striking similarity of strata and fossils on the two coasts. In the 1960’s seismographic data showed that continents and ocean floors rested on vast tectonic plates which were vehicles for continental drift. So, both qualitative and quantitative evidence entered into validation of the theory.
A much more important limit to science has been set by Fr. Jaki:
"Hamlet's question, ‘to be or not to be,’ has a meaning even deeper than whether an act is moral or immoral. That deeper meaning is not merely whether there is a life after death. The deepest perspective opened up by that question is reflection on existence in general. In raising the question, ‘to be or not to be,’ one conveys one's ability to ponder existence itself. In fact every bit of knowledge begins with the registering of something that exists. To know is to register existence. But this is precisely what science cannot do, simply because existence as such cannot be measured.[emphasis added].”--Fr. Stanley Jaki, loc. Cit., p.30.
What this means is that science can not explain itself. Science can not show why it gives us a partial picture of the world expressed mathematically, or to use the Nobel Laureate Eugene Wigner’s apt phrase, science can not explain “the unreasonable effectiveness of mathematics” by an underlying scientific theory. The only justification for this success is empirical—it works!
Therefore science can not answer questions about religion. It cannot neither prove nor disprove the existence of a Godhead, nor the existence of the Trinity. Thus, to say that science “proves” the existence of God, is as much an error as saying it disproves that God exists. We can only say that all that we learn about our world from science is in accord with that world which an omniscient and omnipotent God would create.
*See the linked column by Rabbi Goldson and blog posts by William (Matt) Briggs (Statistician to the Stars)
**I'm thinking of Stephen Hawking, Lawrence Kraus, and most recently, Sean Carroll. I'll be reviewing Carroll's book, "The Big Picture", in another post. It's the best of the lot.
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