[MUSIC] Training in forms of thinking, such as logic and critical thinking, are central to academic life. Universities in many countries see training students to be critical thinkers as a central part of their mission. When solving problem sets in academic contexts, using logic and critical thinking will be expected of you. This forms of thought are useful to have in your mental tool box, and can be used not just for problem solving in academic contexts, but in all walks of life. While critical thinking is the focus of another MOOC in this specialization, this lesson will explore how logic and critical thinking can be used in the area of problem solving. A key attribute of critical thinking is taking a questioning stance and questioning assumptions. Richard Ennis, a leading theorist of critical thinking, lists the ability to judge unstated assumptions as one of his general critical thinking abilities. There are assumptions that lie at the heart of every problem, subject, and academic field. And it is considered good practice to question these assumptions. As an example of questioning assumptions, take the following essay question. How do female engineers influence engineering? What assumption underlies this question? This question implicitly claims that female engineers have a specific influence on engineering due to their gender, without having evidence for this claim. This is an assumption, and to call that into question would be a demonstration of higher level critical thinking skills. Understanding and using inductive and deductive reasoning are also considered crucial to critical thinking, and can be used to solve problems across a wide range of fields. Both forms of reasoning are constructed through premises. These are statements that are taken to be true. And these premises lead to a conclusion. In deductive reasoning, which has also been called top-down reasoning, premises about general truths lead to specific conclusions. The conclusion in deductive reasoning will be true as long as the premises are true. An example of deductive reasoning is the following. Premise 1, all university students can read. Premise 2, Angela is a university student. Conclusion, therefore, Angela can read. In inductive reasoning, we proceed from specific observations to a more general truth, or in a bottom-up direction. An example of inductive reasoning is the following. Premise 1, large falls in the value of shares have led to economic recessions in the past. Premise 2, there was a large fall in the values of shares last week. Conclusion, there will therefore be an economic recession. Inductive reasoning, unlike deductive reasoning, will not always be true, even if the premises are true. In the above example, in this particular case there may not be a recession due to different circumstances. Both forms of reasoning, however, may be useful when thinking through a problem and coming up with a solution. They provide tried and true methods for logical thought, as well as means for evaluating the arguments of others. A final approach to thinking critically about problems is to think beyond the initial problem in terms of levels and systems. In Thomas and Lok's model of critical thinking, for example, thinking systematically, rather than focusing on events, is a key part of critical thinking. Probably the best way to illustrate this is with an example problem. Imagine you work at an inner city health center. Children in the area are presenting to you with higher than normal levels of obesity. What is causing this spike in childhood obesity in the area, and what can you do to address it? You might be tempted to just look at the children's diet and then make recommendations to the parents for how to improve it. However, people's consumption of food rarely occurs in a vacuum. And to truly understand the problem you will need to think more broadly and more systematically. Perhaps you need to investigate the availability of nutritious food in the area. This then may lead you to discover that the children live in a food desert, a part of the country that lacks access to healthy food. You may also investigate the children's socioeconomic background, and find that their families do not have the money or time to buy and prepare healthy food, especially given difficulties of access. You may also find that children's obesity is associated with low levels of education amongst their parents. All of these things are broader systematic reasons for the children's obesity. One creative solution was developed by Josh Troutwine, a food educator who noticed that, despite provision of education programs on healthy eating, low-income families were unable to access the healthy food they wanted in their area. Troutwine and his business partner turned a school bus into a mobile green grocer that could travel to food deserts in the city and provide access to fresh produce. This solution is far more effective than simply recommending that parents improve their children's diets. So in this lesson we have looked at some key aspects of applying reasoning and critical thinking, including questioning assumptions, using deductive and inductive reasoning, and thinking in terms of levels and systems. [MUSIC]