Philosophy of Science

1. Philosophy of Science Textbook Chapter 5 Beginnings chapter 1

2. Story… • Leonard Brand’s walked across the flat face of the rock to the sloping sandstone to study fossilized tracks of small animals. • His student who knew nothing about studying fossils stayed on the flats and ended up discovering some. • Brand the expert “knew” that there weren’t any tracks on the flat area so since he “knew” this he had missed seeing the tracks and walked over them many times. • Thus it is good for people of varying experience to work together as less experienced may have more open minds, while more experienced will take you to an area. Each is apt to discover something that the other will miss.

3. Science and Scripture • Working together can broaden our perspective. • The Bible doesn’t answer ALL our questions, but it does give an important perspective on what to look for and how to think about earth history. • Science and Scripture can both challenge us to think more carefully.

4. Evolution vs Creation • A very hot topic • People often don’t take the time to understand people on each side and their beliefs… • Science in our society today is seen as truth… scientifically proven = truth…?

5. What is Science? • Science is a search for truth through repeated experiments and observations. • Good to ask questions to seek to understand, realizing that not all questions may be able to be answered.

6. Terms • Evolution… what does it mean??? • Broad term, can refer to small biological changes that we can observe (eg. The changes in insects over several generations that make them resistant to certain pesticides.) • This is compatible to creationist views. • But it also can refer to the presumed development of worms, frogs, and monkeys from a common ancestor sometime in the ancient past. • In Beginnings uses the term creationism = interventionism or informed interventionism. • That there has been intelligent intervention in earth history. • Included both the creation and changes (biological changes and geological history) since creation.

7. The scientific process • Knowledge –the things that scientists have learned and the system of organizing that knowledge. • Process –of discovering new things through repeated experimentation and observation. • Definition: The scientific method is a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge.

8. The Scientific Process • Collect Data • Interpret Data • Use this to formulate hypotheses • Conduct experiments to test these hypothesis • Then interpret the results of the experiments. • (Simple things can lead to scientific discoveries) http://www.youtube.com/watch?v=8EUy_82IChY#t=249

9. Deduction

10. Induction

11. More Invisible thing…? • Experiments and the resulting data often answer only part of the question under study, often raise additional questions. • Scientists formulate research plans for further data collection and hypothesis testing. • Scientists publish their research with then is often looked at critically by other scientists and more research often results.

12. Examples • The world is flat.. Christopher Columbus • Geocentric Mode (Aristotle and scientific community) vs. Heliocentric Theory (Copernicus & Galileo)

13. The Role of science • It works best when studying objects and processes that we can observe and measure. • Some truths cannot be tested. • Science has LIMITS in what it can test, understanding these limits helps us decide which questions we can expect it to answer reliably. • Listen… Creation Calls http://www.youtube.com/watch?v=kWooIrU5OwI

14. Beauty, Music, Poetry, and Morality • Limits to science… too complex for science. • We can study how sound waves affect the receptors in our ears, but science can’t reveal to us the real essence of music and of our reaction to it. • Additionally it doesn’t work well using scientific knowledge to discover the morals and values that truly bring happiness.

15. Homework…. • Read Beginnings chp. 2 and write a half page response on it.

16. Science doesn’t give us absolutes • Scientific method will never bring us to the point where we say, “We’ve discovered the truth and it will not change” • Scientists are ever searching for better more complete explanations of nature. • Its always possible that discovery of new data will displace some currently favored theory. We can’t study EVERYTHING… we can’t go back and see what happened exactly in the past. • We study a small sample in a brief moment of time doing our best to explain.

17. The Error of Education • We come out of education believing that certain things we were taught are true. When in school we learn: • First -The facts and theories that are currently accepted by scientist • Second - How to think critically

18. It isn’t realistic to put science into one box, and either believe everything, or doubt everything. Either one of these approaches would be the easy way out since they don’t require thinking. (Brand)

19. No box • Our scientific knowledge is like a progress report along the road to understanding. • Can’t put science in a box and then either believe everything or doubt everything. • Mistake to say I will blindly be apathetic. • Must make the effort to think and evaluate of what we read and see. • You must make some thoughtful personal choices regarding the roles of science and religion in your life and belief system.

20. But the dr. said…???!!! • Bleeding was good… • Smoking was good…

21. March 6

22. Review of chapter 5.4 The Making of a Theory • Early scientific theory • Before the 18th century scientists believed that species were “fixed” and would not change. • After the 18th century that changed. • Lamarck’s Theory (early 1800’s) • Believed in spontaneous generation • Believed that the use, or disuse, of structures would cause these traits to be passed on to the offspring. • E.g. If you workout, your kids will be stronger!

24. The Making of a Theory • Lamarckism– a termed used to describe the concept of inheritance of acquired characteristics

25. Darwin’s Theory • Charles Darwin traveled the world on a ship gathering information which he later published. • Darwin was convinced that if we can alter a species through artificial selection, than the environment may also have selective pressure on wild animals. • He made the connection between selective pressure and the finding that all creatures overproduce offspring. (Malthus)

26. Darwin’s Theory Natural selection – the results of differential reproductive success of individuals caused by variations in their inherited characteristics.

27. The Theory of Evolution by Natural Selection • Darwin noted beak modifications among the 13 similar species of finches on the Galapagos Islands (His key example how the environment caused natural selection)

28. Darwin’s Theory • Natural selection – Cheetah E.g. • In the past there may have been cheetahs with different running speeds. • The faster cheetahs likely caught and died, the faster ones survive. • The faster cheetahs would have more reproductive success and would have a longer reproductive life.

29. Sources of Inherited Variation • Natural selection can only occur if there is variation of traits within the species. The two ways in which variation can occur is: • Mutations and sexual reproduction • Mutations • Mutations are random DNA changes.

30. Sources of Inherited Variation • Mutations • Mutations can be caused by environmental factors such as chemicals, radiation or errors occurring when cells replicate. • Mutations are rare ( one per sex cell) • Mutation effect fitness (reproductive success): • no effect • negative effect • Positive effect

31. Sources of Inherited Variation • Mutations: Accepted understanding • Mutations occur at random, with harmful mutations being more common. No design to it. • Harmful mutations are selected against. Thus, they are eliminated because they decrease the reproductive success of the organism. • Beneficial mutations are selected for and thus, accumulates in the species because they can increase the reproductive success of organisms.

32. Chapter 5.2 Evidence of a Changing earth • Paleontology: the study of fossils • Burrows, footprints, chemical remains can fossilize. • Over 250,000 fossil species discovered (only a fraction of the # of species thought to live on earth at one point) • Story told: • Different species lived on Earth at various times in the past. Almost all species that have lived are now extinct • Complexity of organisms generally increases from the most distant past to the present. • Living species and their most closely matching fossils are usually located in the same geographic region.

33. What should I date it? • Sir Charles Lyell revolutionized geology arguing that most geological change was SLOW and gradual and had been happening over a long time. • Published “Principles of Geology” • Findings based on geological processes of erosion and sedimentation. Life forms went from simple to complex. • His conclusions were not widely accepted at first • Radioactive decay gave a form of geologic clock to help determine the age of the earth. • Oldest fossil ~3.8 billion years. • What about the creation account occurring a short time ago in contrast…? Hold that thought…

34. Radioactive decay gave a form of geologic clock to help determine the age of the earth. • Radioactive decay changes a particular atom (parent isotope) into a daughter isotope of the same or different element. • Physicists measure these decay rates in units called half-lives, the amount of time it takes for ½ of a sample of the isotope to decay and become stable. • Half-life’s are constant for isotopes • Thus are used to measure age of rocks through radiometric dating techniques

35. Hold the phone: 2 propositions… • In the history of radiometric dating theory is good if • A. there are no major changes to be discovered in this field; ie the data is being interpreted correctly. • B. there are principles to be discovered that will lead to a major change interpreting the data. • There is no way for science to test A and B without actually going into the past and future. • So Science assumes A is correct with no evidence for B. • Need to take this on faith… • A Christian convinced of God’s revelations as trustworthy will also make a faith based conclusion.

36. Biogeography is the study of the geographic distribution of life on Earth • Endemic: a species that is found in one location only. • Fossil remains of species that lived a long time ago (more than 150million years??) can be found on many continents. • Fossils of more recent species are found on separate continents: As a result of the location of fossils found it looks like different species evolved independently in isolated parts of the world. (Pangaea)

37. A flood • Lots of species everywhere… • Mass extinction and animals coming from one location. Some can travel to remote places (birds to Hawaii) others can’t. • An animal traveled to a specific location before it left a fossil? • Lots of endemic species in Australia and S. America… hard to reach from Asia Minor. • Would God direct the redistribution of animals after a flood to protect them?

38. The answer is…? • Textbook Practice p. 142 #1,2 • Textbook practice p. 143 #2,3 • Read Beginnings chapter 3 and write a ½-one page summary submit to turnitin.com • Include 3 questions you have about the reading that you would like to know more about. • Video’s to watch, respond, and turnitin.com