Critical Thinking and Science PDF

Critical Analysis and Reasoning in Discipline- based Studies What will you learn in this course?  1. Reasoning logically  2. Analyzing theoretical issues in your subject area  3. Judging ethical problems in daily and academic contexts Course Structure – 3 areas  1. Lo...

Critical Analysis and Reasoning in Discipline- based Studies What will you learn in this course?  1. Reasoning logically  2. Analyzing theoretical issues in your subject area  3. Judging ethical problems in daily and academic contexts Course Structure – 3 areas  1. Logic and critical reasoning  2. Discipline-based studies  3. Ethical reasoning Ch.1 Critical Thinking and Science  What is critical thinking?  The ability to think clearly and rationally about what to do or what to believe.  It includes the ability to engage in reflective and independent thinking. A short video about the importance of critical thinking in university education and career development: https://youtu.be/6OLPL5p0fMg  Suppose you have critical thinking skills, what are your capabilities? You are able to :  understand the logical connections between ideas  identify, construct and evaluate arguments  detect inconsistencies and common mistakes in reasoning  solve problems systematically  identify the relevance and importance of ideas  reflect on the justification of one's own beliefs and values Therefore, a critical thinker:  is able to deduce consequences from what he knows;  knows how to make use of information to solve problems;  to seek relevant sources of information to inform himself. With critical thinking skills, you Gain recognition from stakeholders, e.g. governments, business executives, scientists, or academics etc. that sounds very attractive.  Yet, do you know exactly the meaning of critical thinking ?  Is it a form of creative thinking?  Creative thinking – lead to new insights or perceptions; new products and ideas.  Critical thinking, however, is not necessarily creative.  What is Science?  Is that subjects of physics, chemistry, and biology constituted science while subjects of art, music, and theology do not? We are not asking for a list of activities that are usually called “Science”. Rather, we are asking “ what it is that makes something a science”. Science is an attempt to understand, explain, and predict the world…BUT  What are the challenges? 1. Religions attempt to understand and explain the world. Will you regard religion as a branch of science? 2. Astrology and fortunetelling are attempts to predict the future. Will you describe these activities as science? 3. Historians try to understand and explained what happened in the past. How will you classify history? Treat it as an arts subject or a science one? What are the distinguishing features of Science?  It is the way that Scientists use to investigate the world.  Is a distinctive method of enquiry that are not found in non-scientific disciplines.  Make use of experimentation, observation, and theory-construction that enable scientists to unravel the nature’s secret. Then how could scientists solve problem scientifically?  They do not abandon theories whenever they conflict with the observational data. Rather they look for ways of eliminating the conflict without having to give up the theory.  Scientists are not given experiments. They begin with a problem or question, and have to figure out, through trial and error, how to solve it. What should you do if you would like to learn to think scientifically? 1. Organize and internalize facts 2. Learn terminology 3. Use scientific procedures 4. Continue to use pre-existing frameworks of knowledge and transfer established knowledge they learn in school to new settings/ contexts 5. Learnt to sorts things into given categories Scientific thinking is not a matter of running through a set of steps.  Scientificthinking is a kind of thinking that we continually move back and forth between questions we ask about the world and observations we make and experiments we devise to test out various hypotheses, guesses and models.  What does this result tell me?  Why did this happen?  If this is why, then that should happen when I…….  We have to do a lot of critical thinking in the scientific thinking process, because we must ask clear and precise questions in order to devise experiments that can give us clear and precise answers.  You should seek connections, and access explanations.  Critical thinking is not a matter of accumulating information.  A person with a good memory and who knows a lot of facts is not necessarily good at critical thinking. Q: once again, what is critical thinking? Is it an essential skills that we opt for it? According to the National Council for Excellence in Critical Thinking, critical thinking is: the intellectually disciplined process of actively and skillfully conceptualising, applying, analysing, synthesising, or evaluating information gathered from, or generated by, observation, experience, reflection, reasoning, or communication as a guide to belief or action. Zeegers, P., Deller-Evans, K., Egege S., and Klinger, C. (2008). Essential Skills for Science and Technology. Oxford University Press.  Analysis What do we do when we analyze something? The word comes from the Greek word ἀνάλυσις (analusis), roughly meaning decomposition. Analysis is a bread-and-butter method in tackling problems in all subjects, especially in the academic context. For example, in reading comprehension, we are asked to analyze what is said in the passage; whereas in chemistry, we analyze the constituents of a compound. There are at least three aspects of analysis. 19  I. Regressive  Working back to first principles so that something can be proved or constructed.  For example, we believe that certain basic principles can help us derive all other important results in a subject: in some contexts, we call those first principles axioms. 20 Examples Dalton’s atomic theory in Chemistry?? Isaac Newton’s three laws of motion and his famous principle of universal gravitation in Physics?? Charles Darwin’s discovery of the theory of evolution by natural selection in Biology??  II. Decompositional  Breaking down a complicated concept into smaller parts  In biology, we understand an organism in terms of its genetic codes. Of course, in chemistry a compound is decomposed into its elements. 22  III. Interpretive  Interpretive Analysis involves a creative dimension requiring us to frame a problem in terms of new concepts and the relations amongst them.  Humanities students are often asked to interpret a text. 23 What about you, as a science student?  Which two aspects of analysis are more common in the context of science? 1. Regressive 2. Decompositional Why critical thinking is needed?  To make the best decision in every important issue.  To be achieved by evaluating arguments’ pro and con. The ultimate objective in thinking critically is to come to conclusions that are correct and to make decisions that are wise.  The purpose of thinking critically is to come to correct conclusions. In the realm of science, a core set of characteristics in critical thinking involves:  Analysis  Interpretation  Inference  Explanation  Evaluation  Self-regulation Science and the pursuit of knowledge  Critical thinking is also linked to the “scientific method”, an approach to science credited to Francis Bacon (1561-1626).  The pursuit of science is about discovering new things, and determining the laws that govern them.  Sir Isaac Newton is the founder of the “scientific method”. He proved his claims by using scientific methods of observation, hypothesis, and experimentation. The scientific method 29 The scientific method Draw a conclusion 30 Both theory and hypothesis are explanations of what you observed, what are the differences between theses two terms? What is the definition of law? 31 Hypothesis  A tentative explanation for a set of observations /questions regarding cause and effect in a specific situation  Testable  Can be rejected or corrected 32 Theory  A well established explanation of the experimental observations  A unifying principle that explains a set of observations and can accurately predict the results of future observations or experiments 33 Law  A statement describes the relationship between phenomena that is always the same under the same conditions.  Has a broad application  E.g. Newton’s law of Motions 34 The four basic steps in Scientific method: 1. State the problem - a problem can't be solved if it isn't understood.  Curious Observation e.g Is there a Problem? 2. Form a hypothesis - a possible solution, formed after gathering information about the problem.  Search, Explore, and Gather the Information. Make the Educated Guess. Generate Creative and Logical hypotheses 35  Basic steps in scientific methods 3. Test the hypothesis - an experiment is an organized set of procedures performed to determine if the hypothesis solves the problem or not - Challenge the Hypothesis 4. Draw conclusions - in it's simplest form, the conclusion will be "yes“- the hypothesis was correct, or "no" - the hypothesis was not correct - Reach a Conclusion 36  Remember We have to do a lot of critical thinking in the scientific thinking process, because we must ask clear and precise questions in order to devise experiments that can give us clear and precise answers. When we think, we will inevitably ask questions. What are the probing questions that we shall ask in performing experiments? Examples of general probing questions:  What exactly are you doing? Why?  What results do you expect? Why?  Have you designed any controls for this experiments? / Why do you have to use the same amount of liquid for both tests? / Why do these have to be the same temperature? Size? What would happen if they weren’t Examples of probing questions in making calculations or taking measurements:  What are you measuring? Why? What will that tell you?  What numbers do you need to record? In what units? Why?  What equation are you using? Why? Which numbers go where in the equation?  What does the answer tell you?  What would a different answer mean? Examples of probing questions in studying anatomy:  If this part of the body has this function, what would happen if it no longer functioned fully or at all? Why do you say so?  What would that be like for the person? What if it functioned on “overdrive”?  What other parts of the body would such breakdowns affect? Why? Examples of probing questions in Biology:  How important is this distinction? Let’s look at our chart of categories of living things. Where on the chart is this distinction? Why?  What distinction is more important? Why? Less important? Why? Sample: Why is the distinction between vertebrates and invertebrates more important to zoologists than the distinction between warm- blooded and cold-blooded animals? Be prepared to be asked to explain justification for scientific claims.  Why does your text say this?  How would that prove this conclusion?  Could we explain these results another way?  How could we tell which was right? What would we have to do? Why? Task: Where do plants get their food?  From water, soil, carbon dioxide gas  Misunderstood the concept of “food” for plants  Crucial idea: plants make their own food. 3 important elements to critical thinking that emerge from the history of science:  Logic  Argumentation  Proof or evidence to support one’s ideas. Critical use of all 3 elements enable you to discern: - what scientific statements are mostly to be true; - What scientific statements there are good reasons to doubt; - Which scientific statements we cannot evaluate. In the sciences…  We focus on developing knowledge of the physical world and the laws that govern it.  All good research contributes to our knowledge based by claiming something new or confirming previously made claims.  E.g. plants metabolise carbon dioxide  E.g. water boils at 100C  These claims can be either true or false. Critical thinking in the sciences tends to focus on Problem solving. We cannot rely on perception to give us an accurate picture of the world because it is too easy to be mistaken.  The most important criterion for knowledge claims is justification, the evidence, proof, or reasons one has for supporting a claim.  The stronger or more convincing that evidence, or the more logical or persuasive the argument, the more likely the claim is true.  Examples To convince you to learn critical thinking skills Why critical thinking is important?  Books, lectures, and articles contain more than information. You need to sort fact from opinion or interpretation. Assess the argument.  Writers express different or contradictory views – you need to compare and contrast.  Can express bias or limited cultural perspective – you need to assess for objectivity.  Ideas can conflict with personal beliefs, ethics and knowledge – you need to be personally objective.  Knowledge claims rely on the strength of the evidence used in support – you need to assess justification or proof.  In contrasting your own claims, you need to be clear, convincing, and logical. Evaluation of evidence  In the mid 19th century, there was a particularly severe outbreak of cholera in London. It was widely believed at the time that cholera was an airborne disease and that the outbreak was caused by the dirty air. A major engineering project was undertaken to improve the quality of air by channeling London sewage out of the city in the belief that this would remove the offending cholera bacteria. On completion of the project, the incidences of cholera disappeared, thus confirming that cholera was indeed an airborne disease.  Ten years later, the cholera returned. Further investigation discovered that eels had been trapped in some of the water pumps and died, contaminating the drinking water. Once these were sealed off form use, there were no new outbreaks of cholera. TASK Was cholera an airborne or a water-borne disease?  It turned out that cholera was, in fact, a water-borne disease. To sum up…..  It is easy to make mistakes, jump to the wrong conclusion, or jump to conclusions too quickly.  Developing critical thinking skills by learning how to assess the accuracy, reliability, and quality of the evidence presented can help reduce error and to draw a correct conclusion.