Deductive reasoning is a type of logic that uses general principles to make specific predictions or conclusions. It is the opposite of inductive reasoning, where general principles are inferred from specific observations. Both types of reasoning are used in the process of generating and testing hypotheses. For example, a scientist observes that butterflies are attracted to red flowers, but not yellow ones. Using inductive reasoning, they formulate the hypothesis that butterflies prefer specific flowers based on the color of their petals. The scientist then employs deductive reasoning to predict a number of possible results and design experiments to test the hypothesis. In this case, changing the flower's petal color should alter the butterfly's attraction, but changing its scent or its petal shape should not. The results of the experiment may lead to further inductive hypotheses and deductive predictions. For instance, the scientist might observe that butterflies also tend to avoid flowers with pointed petals. In this way, both inductive and deductive reasoning are used to help expand our scientific knowledge and understanding.