Teaching a Christian Worldview in the Math Class Date: February 11, 2010 Presenter: Brett Edwards Contact: bedwards@accak12.org “The chief aim of all investigations of the external world should be to discover the rational order and harmony which has been imposed on it by God and which He revealed to us in the language of mathematics.” – Johannes Kepler In my 9 years of teaching mathematics, the most difficult thing for me has been how to communicate to my students a distinctly Christian worldview of mathematics. This is not to say I haven’t struggled with how to teach a particular concept or idea or how to control a wild class, etc. By far the thing I have spent the most time blankly staring at a blank lesson plan is how to help students see how what we do in the math class relates to their lives as Christians. Q. Why is it so difficult for the Christian math teacher (or at least myself) to know how to inculcate a Christian worldview of mathematics? 1. We were not taught to think this way ourselves when we were students. o I am a product of a public school system that taught me God had nothing to do with academics and especially not mathematics 2. We have a misconception about what teaching a Christian worldview constitutes. o Teaching a student in Bible class who the author of Romans is is not inculcating a Christian worldview o Chapel once a week does very little if the child is not immersed in the gospel the rest of the week o A daily Bible verse or prayer before math class is NOT inculcating a Christian worldview o Teaching the students to think of the cross every time they see an addition sign is NOT teaching Biblical worldview o There are many Bible teachers that are communicating a lot of Biblical information to there students but they are not giving their students an ability to analyze the world through a Christ centered perspective o The point is that Christian worldview is difficult in EVERY class because most of us are children of Caesar trying to teach in a way that we were NOT taught ourselves 3. Our students have not been prepared by their own parents, their own churches and even their authorities within the school to think of mathematics as an area where God applies o I was told by a teaching friend of mine who is a Bible teacher and also teaches at a Christian school. He said that once when having a conversation with this principal, the principal told him how sorry he felt for the science and math teachers at the school. My friend asked why and the principal of a conservative Christian school said that math and science teachers don’t get to teach about the “important” matters of life. It’s the Bible teachers that get to teach the important things while math teachers teach the subjects unrelated to spiritual things! o This is not helped when week after week, chapel messages emphasize that “while math, science and history are important… the most important thing they can do is give their life to Jesus” please don’t hear what I am not saying Sure if I had a choice, I would rather my students understand the gospel than the Pythagorean theorem but I don’t think it’s appropriate to phrase it this way It’s like saying “while being nice to your neighbor, loving the orphan, and respecting your elders are important things… the most important thing you can do is give your life to Jesus” 4. We want to believe there is a magic formula, a 3 step process to teaching Christian worldview in mathematics o I naively thought that I just needed to get my hands on the right book, employ a few nifty techniques and within 6 weeks my students would be seeing Jesus in every equation the worked out o We have to retrain our minds and see how we can find the Lord in the math class room So, here we are, we have established that it is a difficult task. I now embark on a the daunting task of trying my best to tell you what I have learned in my short 9 years of teaching mathematics how we can communicate a Christian worldview of mathematics. How do we communicate a Christian worldview in mathematics? Is God silent? as James Nickel asks in his book. I. Emphasize the presuppositional aspect of math. II. Explore and emphasize the mysteries of mathematics. III. Teach students to see math as a quest to find the order and harmony of God in nature. IV. Instill a passion for truth and beauty in our students. V. Last resort, math class is a very valuable training ground for the mind. I. Emphasize the presuppositional aspect of math a. Students must understand that not everything is proven in mathematics o It is critical for them to understand this because the world tells them from day one that math and science does not accept anything on faith which couldn’t be farther from the truth o All math and science performed is based on presuppositions, things assumed to be true b. Let’s see an example relating mathematical proof and how our student’s might use this style of reasoning to give support for their faith in the Christian God o Euclid’s Elements offer us a great example of how even the mathematician must grant some things as true without proof. The foundational textbook for Western mathematics is Euclid’s Elements, 436 propositions proven with a rigorous logic still respected by all mathematicians and scientists today However, to even start the textbook, Euclid grants that he is unable to prove anything unless he assumes some things to be true The things Euclid assumes to be true are 5 postulates and 5 common notions… he was unable to prove them but he would not be able to make mathematical sense of the world if he didn’t first assume them to be true. This is where student’s must see the connection to their faith in the Christian God. Even the Geometer must have “faith” in these 5 postulates if he wants to make sense of the physical world. Christians must admit their inability to prove mathematically or scientifically the existence of God But if our students can see that only when they accept God as true, the same way Euclid accepted his 5 postulates as true, can they then make sense of the world… they will then be armed with the reasoning skills to attack an unbelieving world Looking at our world with an atheistic worldview does not give the foundation to understand good and evil, what is beautiful, what is true, etc. o Greek Geometry was focused on a logical process of If… then… statements to give support for a particular proposition. For example, let’s see how this reasoning works with proposition 1 from Euclid’s Elements. o o o o After constructing the above with compass and straight edge, Euclid reasons like so… If AB and AC are both radii of circle A, then they are equal. If AB and BC are both radii of circle B, then they are equal. If AC is equal to AB and BC is equal to AB then AC is equal to BC. If all the sides of triangle ABC are equal, then ABC is an equilateral triangle. In the same manner, we as Christians give justification for our faith. If the Christian God is true, then the Bible is true. If the Bible is true, then man is made in the image of God. If man is made in the image of God, then it is a sin to kill man. I am not arguing for a robotic like defense of the faith. In conversation, the Christian student would not want to rattle off a bunch of “If… then…” statements thinking the goal is to logically corner their unbelieving friend. However, the reasoning that it takes to understand mathematical proofs is the type of reasoning that Jesus, Paul and others use to defend the Christian faith Obviously there are many “if… then…” type statements in the Bible but let’s look at two Biblical examples of such reasoning skills “For those whom He foreknew, He also predestined to become conformed to the image of His Son, so that He would be the firstborn among many brethren; and these whom He predestined, He also called; and these whom He called, He also justified; and these whom He justified, He also glorified.” If a, then b. If b, then c. If c, then d. Thus if a, then d. Our students must be able to communicate this type of thinking and the math class is a great place to cultivate such skills. Let’s now look at a related aspect of mathematical reasoning we get from Greek mathematics. Euclid’s Elements also introduces an ingenious method to proving propositions called a reduction ad absurdum which is a proof by contradiction Proposition 6 of the first book of the Elements is Euclid’s first use of the reduction ad absurdum If we know that angles ABC and ACB are equal, we want to prove that AB will be equal to AC In order to do this, Euclid assumes that AB and AC are NOT equal He assumes the opposite of what he is trying to prove knowing that this will create a contradiction thus proving the contrary If AB is not equal to AC, then one must be greater, we will pick AB to be greater. If AB is greater, then there is a point on AB which will make DB equal to AC. When looking at triangle ABC and triangle DBC , we can see that AC is equal to DB and BC is common to both triangles and angle DBC is equal to angle ACD, we can then conclude that triangle ABC (blue) is equal to triangle DBC (red) because of proposition 4 (SAS) What’s the problem? This is absurd! This can’t be true and we then retrack each step finding that the only fault in our reasoning can be our first step. o How does a reduction ad absurdum relate to our Christian faith? It has a very importation relationship. In the same way that we reason above, we can follow the line of reasoning that results from unbelief If we assume the opposite of what we believe to be true, mainly that there is no God and the atheistic evolutionary worldview is true, what does this assumption require. If there is no God, then the Bible is not true. If the Bible is not true we are not made in the image of God. If we are not made in the image of God, then man is an animal. If man is an animal, then moral absolutes make as much sense as they do in the animal kingdom. If moral absolutes are meaningless, then there is no good and evil or right and wrong. o Few unbelievers would be willing to accept such a conclusion but where is the logic wrong? c. Even mathematicians are forced to except certain things on faith “To Descartes this result, God’s existence, was more important for science than for theology, for it afforded the possibility of solving the central problem of the existence of an objective world.” - Math Historian Morris Kline (Mathematics and the Search for Knowledge) d. Faith is required to play both the game of mathematics and the game of a meaningful life i. What the moral atheist and the unbelieving mathematician have in common o They are both inconsistent with their presuppositions o The moral atheist claims we there is no God, we come are descendants of primordial goo and we are simply another mammal. o After accepting these presuppositions, they then inconsistently adopt an absolutist moral world where there is good and evil, right and wrong. o Descartes rightly understood that the existence of an objective world could only be true if God were true. e. Conclusion - Our students need to learn in the higher levels of mathematics that all understanding (even in the sciences) is presuppositional, based on things assumed to be true with no ability to prove them. Yet, it is only when these things, Euclid’s postulates or the existence of God, when accepted as true that we can then make sense of the world around us. II. Explore and emphasize the mysteries of mathematics a. Connect this lack of understanding with the only solution an infinite God “Oh, the depth of the riches both of the wisdom and knowledge of God! How unsearchable are His judgments and unfathomable His ways!” – Romans 11:33 b. The more we learn in the arena of mathematics, the more we find out how much there is we truly don’t know. c. Goldbach’s conjecture states that Every even integer greater than 2 is a Goldbach number, a number than can be expressed as the sum of two primes. o 4 = 2 + 2 (both 2 and 2 are primes) o 6 = 3 + 3 (both 3 and 3 are primes) o 8=3+5 o 60 = 17 + 43 o Goldbach’s conjecture has been proven true by computer for all even numbers up to 1018 or 1,000,000,000,000,000,000. o But this still does not constitute mathematical proof. It is still a mystery. d. Another goal for number theorists has been to find a formula that will generate only prime numbers. o One of the great number theorists of all time, Leonhard Euler attempted to solve this problem with the formula n2 + n + 41 Starting with n=0, it worked all the way for n=0, n=1, n=2… n=39 It was when n=40 that the formula finally failed (41 * 41 = 1681) n2 + n+ 41 n Outcome n … Outcome n … Outcome n … Outcome n … Outcome 0 41 Prime 1 43 Prime 21 503 Prime 41 1763 Composite 61 3823 Prime 81 6683 Composite 2 47 Prime 22 547 Prime 42 1847 Prime 62 3947 Prime 82 6847 Composite 3 53 Prime 23 593 Prime 43 1933 Prime 63 4073 Prime 83 7013 Prime 4 61 Prime 24 641 Prime 44 2021 Composite 64 4201 Prime 84 7181 Composite 5 71 Prime 25 691 Prime 45 2111 Prime 65 4331 Composite 85 7351 Prime 6 83 Prime 26 743 Prime 46 2203 Prime 66 4463 Prime 86 7523 Prime 7 97 Prime 27 797 Prime 47 2297 Prime 67 4597 Prime 87 7697 Composite 8 113 Prime 28 853 Prime 48 2393 Prime 68 4733 Prime 88 7873 Prime 9 131 Prime 29 911 Prime 49 2491 Composite 69 4871 Prime 89 8051 Composite 10 151 Prime 30 971 Prime 50 2591 Prime 70 5011 Prime 90 8231 Prime 11 173 Prime 31 1033 Prime 51 2693 Prime 71 5153 Prime 91 8413 Composite 12 197 Prime 32 1097 Prime 52 2797 Prime 72 5297 Prime 92 8597 Prime 13 223 Prime 33 1163 Prime 53 2903 Prime 73 5443 Prime 93 8783 Prime 14 251 Prime 34 1231 Prime 54 3011 Prime 74 5591 Prime 94 8971 Prime 15 281 Prime 35 1301 Prime 55 3121 Prime 75 5741 Prime 95 9161 Prime 16 313 Prime 36 1373 Prime 56 3233 Composite 76 5893 Composite 96 9353 Composite 17 347 Prime 37 1447 Prime 57 3347 Prime 77 6047 Prime 97 9547 Prime 18 383 Prime 38 1523 Prime 58 3463 Prime 78 6203 Prime 98 9743 Prime 19 421 Prime 39 1601 Prime 59 3581 Prime 79 6361 Prime 99 9941 Prime 20 461 Prime 40 1681 Composite 60 3701 Prime 80 6521 Prime 100 10141 Prime Euler’s formula was later found by a computer to generate prime numbers 47.5% of the time which is surprisingly good “It will be another million years, at least, before we understand the primes.” – Hungarian number theorist Paul Erdös e. The mystery of Pi o Someone could easily do an entire lecture or even series on the mystery of Pi. o Pi is this remarkable number, with no pattern that makes sense of the natural world. o No mathematician in the world can make sense of why this crazy number seems to pop up so much. o One remarkable instance of Pi in nature is a study conducted by Hans-Henrik Stolum, an earth scientist at Cambridge. He has found that the ratio of between the actual length of rivers from source to mouth and their direct length as the crow flies comes out to an average value slightly greater than 3. In fact, this ratio is approximately 3.14 Why is this? God has hidden His signature all over the world for our pleasure. f. The mathematician Kurt Gödel proved that a complete and consistent mathematical system was an impossible task. He proved it was impossible with two theorems… o First theorem of undecidability - If axiomatic set theory is consistent, there exists theorems that can neither be proved or disproved. o Second theorem of undecidability - There is no constructive procedure that will prove axiomatic theory to be consistent. o To sum this up, Gödel is making that statement that no matter what set of axioms are being used, there would be questions that mathematics can not answer, completeness can not ever be achieved by means of mathematics. o Gödel’s theorems along with much of the mathematics of the last 200 years have been a tough pill to swallow for many mathematicians o Many mathematicians and scientists, the champions of human reason, had believed that reason and logic would soon be able to solve all the mysteries and riddles of the world. o They envisioned a time when reason would unveil all secrets but Gödel’s theorems argued that even human reason was unable to unlock all the mysteries of the world. o Is this a problem for the Christian? Of course not! “…How unfathomable are His ways!” – Romans 11:33 We confess the inability of human reason to understand the depths of God We still ought to do our best to understand what we can all the while confessing that the finite man can never fully understand an infinite God. III. Teach students to see math as a quest to find the order and harmony of God in nature. “For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse.” – Romans 1:20 a. The explorations in math give us a greater understanding of the nature of God b. I want to look at two illustrations where we see a discovery of the order and harmony of God in nature. c. The first was by Pythagoras, an unbeliever, who still believed the world to have been created in an orderly fashion with mathematics at its foundation. o Legend has it that one day on his way to work, Pythagoras was passing a blacksmith when he heard beautiful and harmonious sounds coming from the anvils being used by the blacksmith. o He was convinced that there was a scientific law creating such harmonious sounds. o He investigated the anvils and found out that harmonious sounds were created by hammers that were simple ratios or fractions of each other. o Thus, the hammer that was ½ another or 2/3 would create a harmonious sound while a hammer that was not a simple ratio of the other would create disharmony. o This idea was then expanded to apply to stringed instruments as well. d. In the second illustration we see how a scientist explored the laws of nature in an effort to learn more about the Creator is in the man Johannes Kepler. e. Kepler, lived from (1571-1630), and is best known for his work as an astronomer . f. Kepler believed the world was designed by God in accordance with a mathematical plan. He said; “Thus God himself was too kind to remain idle, and began to play the game of signatures, signifying his likeness into the world; therefore I chance to think that all nature and the graceful sky are symbolized in the art of geometry.” - Kepler g. It was the relentless goal of Kepler to find these signatures. One of these signatures he postulated was that the orbits of the six known planets of the time had a relationship to the 5 Platonic solids (the cube, tetrahedron, etc.) o After great efforts to make this connection, Kepler abandoned the effort seeing that the data did not match his hypotheses h. However, Kepler continued in his quest to discover God’s handwriting on the universe and did so in his most famous contribution to astronomy with his three laws of planetary motion. 1. The first law was revolutionary. It confirmed the Copernican idea that the Earth revolved around the sun but departed from Copernicus and rightly stated that the Earth does not rotate in a circle but in an ellipse. Both Ptolemy and Copernicus resorted to what are called epicycles to explain a certain “unexplainable” phenomena that was seen Kepler, convinced their was a more beautiful answer to the question, abandoned the idea of epicycles and this directed him to the idea of ellipses which was true He also noted in the first law that the Sun was at one “focus” of the elliptical paths and the other point is merely a mathematical point with nothing there 2. His second law also departed from a long held belief in constant velocities of the planets when Kepler stated that Earth revolved on an ellipse but at varying velocities. Faster when nearer to the sun and slower as the Earth went away from the Sun. Included in his second law is the understanding that the area of sectors covered by the Earth were equal for equal time periods. See illustration. This finding overjoyed Kepler and reaffirmed his belief that God had used mathematical principles to design the universe. 3. Kepler’s third law states that T2 = kD3, where T is the period of revolution of any planet and D is its mean distance from the sun and k is a constant which is the same for all planets. After stating this Third Law in his book The Harmony of the World, Kepler broke forth in praise of God saying; “Sun, moon, and planets glorify Him in your ineffable language! Celestial harmonies, all ye who comprehend His marvelous works, praise Him. And thou, my soul, praise thy Creator! It is Him and in Him that all exists. That which we know best is comprised in Him, as well as in our vain science.” – Kepler i. I want to encourage little Kepler’s in the classroom seeking truth and beauty knowing that harmony exists in the Universe because they know God has created it according to His nature. His nature being that of truth, beauty, harmony and order. IV. Instill a passion for truth and beauty in our students a. Students need to see the value in finding truth in every discipline o The great Greek mathematician Euclid, when asked by a student the purpose for what he was learning looked at his slave and said “Give the boy a penny since he desires to profit from all that he learns.” o Euclid is saying, truth is worth learning regardless of what it profits you. o We should not tolerate or accept such an attitude in the math class. b. Our students should desire to seek out and find that which is beautiful and the natural world provides all kinds of beautiful secrets of they will seek them out. c. One of the many places in the natural world where we see this harmony and order of the natural world is in one of the most notable number sequences in math; the Fibonacci sequence o Leonardo of Pisa (1170-1250) referred to himself as “son of Bonacci” or “Fibonacci” which is what he is known as today o It was in his text Liber Abaci that Fibonacci introduced Arabic numerals o In his book Liber Abaci, he wrote what may be the most famous sequence of numbers, named after him 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89…. Each of the numbers is the sum of the two previous numbers o One of the phenomenal things about the Fibonacci sequence is its appearance in the natural world If one were to count the two different sets of spirals on a pineapple, they would find the two values to be two consecutive Fibonacci numbers The same is true for the spirals on a sunflower head and pinecones d. To help nurture a child’s struggle in a certain discipline we tell them they must be gifted in other areas and not mathematics. This logically creates a student averse to whatever discipline in which they struggle. “Mr. Edwards, I’m just not a math person.” You’ve made a choice to not be a math person. This choice has likely been encouraged by parents, teachers, etc. e. The idea of a Renaissance man or woman has vanished from the way we teach. o The world tells us we need to begin specialization in our children as early as possible. o If the student is not gifted at math and will not get a job in that discipline, the world argues that there is little value in them investing so much time and effort. o We must resist this thinking and tell our students that the thinking required for upper level mathematics is valuable for all students. V. Last resort, math class is a very valuable training ground for the mind a. b. c. d. e. f. g. h. i. “And do not be conformed to this world, but be transformed by the renewing of your mind, so that you may prove what the will of God is, that which is good an acceptable and perfect.” – Romans 12:2 I have had many a student argue to the nth degree why math is worthless yet I still have yet to hear a student argue that thinking is a worthless endeavor Not a single student of mine has ever expressed a sincere desire for ignorance Mathematics is mental weight lifting preparing them mentally for every area of life We are teaching them to be Christian problem solvers in the math class Do not allow your students to think the problem solving in the math class does not apply to any other area of life The student that creatively finds solutions in the math class will be the same creative problem solver in family disputes, the same person that finds a solution to a business dilemma, that finds a creative method to finding justice in the court room, that brings peace to a church in turmoil… The determination, the will to find a solution that a teacher can cultivate in a classroom can not help but over flow into other areas of the student’s life I still have a hard time understanding how a student can fail at understanding how to develop a proof in the geometry class yet develop a strong logical argument in an English paper. Even Lincoln understood the value benefits of mathematical reasoning skills when he said in an autobiographical sketch the following; “I said, “Lincoln, you can never make a lawyer if you do not understand what demonstrate means”; and I left my situation in Springfield, went home to my father’s house, and stayed there till I could give any proposition in the six books of Euclid at sight. I then found out what “demonstrate” means, and went back to my law studies.” – Abraham Lincoln - The first six books of the Elements contain 173 propositions, it’s hard to believe but who would doubt honest Abe Mastery in the math classroom can only help our students in whatever area they will venture in the future. Conclusion “Mathematics is the language in which God has written the universe.” - Galileo Mathematics is understanding in greater detail the handiwork of God. It is learning how our Lord has created all things. We can give our students a Christian understanding of this world if we can I. Emphasize the presuppositional aspect of math. II. Explore and emphasize the mysteries of mathematics. III. Teach students to see math as a quest to find the order and harmony of God in nature. IV. Instill a passion for truth and beauty in our students V. Last resort, math class is a very valuable training ground for the mind