Truth 2

1. Truth 2 Week 04

2. In today’s lecture… • Recap • The Man form Earth • Science, faith and truth

3. Recap • The correspondence theory and the coherence theory • Russell’s argument against the coherence theory of truth • Relativism

4. Recap • The correspondence theory of truth states that the truth or falsity of a statement is determined by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world.

5. Recap • In contrast, the coherence theory of truth which holds that the truth or falsity of a statement is determined by its relations to other statements within a belief system rather than its relation to the world.

6. Recap • Russell argued that ‘coherence’ alone cannot be a sufficient condition for ‘truth’ because: [1] some of our existing beliefs may not be accurate representations of reality, so judgment based on our existing beliefs alone is unreliable;

7. Recap [2] a knowledgeable (知識豐富的) person can make up an untruestory that is perfectly consistent with our existing beliefs; [3] there are many different, incompatible (不相容的) belief systems in this world; these belief systems are more or less internally consistent, but they cannot all be true.

8. Recap • Relativism (相對主義) is the view the all truths are subjective. There is no such thing as absolute or objective truth. • Different groups, societies and cultures have different ideas and standards of truth. According to relativism, truth is relative to groups, societies and cultures.

9. Recap • Kant (康德) rejected relativism by arguing that people of all societies and cultures must use the same basic concepts (‘object’, ‘identity’ and ‘causality’, etc.) to make sense of the world. • Relativists, on the other hand, believe that people who speak different languages have different ways of making sense of the world.

10. The Man from Earth

11. The Man from Earth • In the film The Man from Earth, John Oldman’s friends are not sure whether he is [1] telling the truth, [2] lying, or [3] crazy (or under the influence of drugsor alcohol). • They soon realize that [3] is probably not true, but they find it difficult to make up their minds between the other two possibilities.

12. The Man from Earth Why do some of John Oldman’s friends and colleagues think that he is not telling the truth? Imagine you are one of the people talking with John Oldman. How would you determine whether the things he says are true or not?

13. Science, faith and truth The film not only highlights some of the philosophical issues concerning knowledge and truth, but also draws attention to the troubled relationship between science and religion.

14. Science, faith and truth • In the film, John Oldman says he doesn’t follow any known religion becausehe thinks thatreligions are mostly ‘hogwash’ (無稽之談). • For example, he thinks the Buddha (佛陀) had many great ideas, but it was mistaken to turn those ideas into a religion.

15. Science, faith and truth • According to John Oldman, creation myths (創造宇宙的神話) were very common inprimitive societies (原始社會) because of people’s natural desire to attempt to make sense of the universe. • These myths became the first religions when large groups of people believed in them.

16. Science, faith and truth • John Oldman quotes the words of French mathematician and astronomer Pierre-Simon de Laplace who argued that God has no place in the modern scientific worldview. • When Laplace presented his theory of the universe to Napoleon, Napoleon asked: “Where does God fit into your theory?” Laplace replied: “I have no need of that hypothesis.”

17. Science, faith and truth Do you agree with John Oldman’s view of religion? Why do people have religion? Why are there so many different religions? How can we know which religion is true?

18. Science, faith and truth • All religions are based on faith. But what is faith? • Simply put, faith is a non-rational (非理性的) belief in some proposition. Faith is belief that does not rest on logical proof or objectiveevidence. To believe something on faith is to believe it in spite of, or even because of, the fact that we do not have sufficient evidence for it.

19. Science, faith and truth Many of our beliefs are not supported or confirmed by evidence. Can suchbeliefs be a source of true knowledge?

20. Science, faith and truth • People often look to their faith to validate (確定、驗證) beliefs and help them decide what is true. Peopleoften assert that something is true justbecause it is something they have faith in. • However, we cannot make something true simply by believing it to be true. The fact the we believe something does not justify our believing it.

21. Science, faith and truth • Faith by itself is merely a firm conviction (堅決的信念), but a firm convictionwithout the support ofreason and evidence is no guide to truth. • Since belief without evidence is not rational, faith is not rational. Only rational beliefs can be a source of true knowledge. So faith cannot be a source of true knowledge.

22. Science, faith and truth • Humans have a great hunger for explanation, which is why we have so many different religions that aspire to provide explanations. • Religion is largely based on faith, whereas modern science is largely based on reason and evidence. That is why scientific explanations are usually superior to those offered by religion.

23. Science, faith and truth • Science tries to understand the world by identifying general principles that are both explanatory and predictive. • The goal of scientific research is the production of laws and theories that yield successful predictions and understanding of a wide range of phenomena(現象).

24. Science, faith and truth • Francis Bacon (1561-1626), father of the modern scientific method, argued that science was the process of deriving the laws of nature from a body of observations by induction, the process of inferring (推論) a general law from a sufficiently large number of particular instances (個案).

25. Science, faith and truth • Inductive generalization, however, is not always reliable due to the problem of induction (i.e. the problem of black swans). • Thus, to ensure the reliability of scientific knowledge, theories and hypotheses have to be put to test. (A hypothesis is a theory that can be tested using the scientific method.)

26. Science, faith and truth • Basically, the ‘scientific method’ can be seen as a 3-step process: [1] Observation: e.g. You observe that water freezes when the temperature drops to zero or below.

27. Science, faith and truth [2] Inductive generalization: e.g. You see this happen again and again, so you infer that water freezes every time the temperature drops to zero or below. You now have a new theory or hypothesis: The freezing point of water is zero degree Celsius.

28. Science, faith and truth [3] Hypothesis-testing: e.g. Based on your theory or hypothesis, you predict that when winter comes and the temperature drops below zero, the water in the lake will freeze. And you check to see whether the prediction is verified (被證實) or confirmed.

29. Science, faith and truth • What if the prediction turns out to be wrong? • You look for other factors or variables (變數), formulate a new hypothesis, and test it against reality to see whether it is better than the previous one.

30. Science, faith and truth • The process is a constantly interactive one between making observations, drawing conclusions, making predictions, and checking them against further evidence. • Science, in other words, is a feedback process: it learns from its own mistakes.

31. Science, faith and truth • All knowledgein science is provisional(暫時性的); scientists must continue formulating and testing new hypotheses. • The scientific method is self-correcting, and as such it is our most reliable guide to the truth.

32. Science, faith and truth • To sum up:the scientific method consists of the collection of data through observation and experimentation, and the formulation and testing of hypotheses.These steps must be repeatable (可重複的) in order to produce more reliable knowledge andpredict future results more accurately.

33. Science, faith and truth What is the biggest difference between science and religion? Is there any difference between trust in science and faith in religion? Some people suggest that science tells us how the world works, but it is religion that gives the world meaning. How far do you agree with this view?

34. Read! • Download and read the article titled ‘Fact versus Faith’ on the course website: filmandphilosophy.weebly.com