Scientific Methods – Inductive & Deductive Reasoning, Hypothetico-Deductive Approach
The second class of the semester was about to begin and I sat there still feeling that my time was being wasted doing this course, as I am a law student. In this session, the lecturer introduced to us some of the methods that are used in the practice of science: the inductive, deductive and hypothetico-deductive methods. She linked these scientific methodologies (i. e. the ways scientists gather scientific knowledge) to the objectivity of science. In class, we discussed the objectivity of science to be the claims, methods and results of science not being influenced by particular perspectives or personal interests (lecture slides). Furthermore, we explored definitions, examples and the use of each method in science, as well as identified some of their strengths and limitations. The lecturer also advised us to apply each method to our lives and to each of our respective disciplines. Inductive and deductive methods were dealt with first.
At the beginning, I had challenges grasping the meanings of these terms; however, they started to become clearer when the lecturer brought both methods together as well as used examples. I realized that they basically had opposite meanings; thus, making it simple for me to define the methods and draw comparisons. The inductive method starts with many observations of nature, with the goal of finding a few, powerful statements about how nature works. On the other hand, the deductive method starts with a few true statements with the goal of proving many true statements that logically follow from them. For instance, if we examine enough feral cats we can generalize that feral cats are a rich source of fleas (induction). If, like Robinson Crusoe, we come across footprints on the beach of a desert island, we can conclude from our knowledge of the human footprint that another human is or was on the island (deduction).
The class became intriguing when the lecturer asked students to give examples of one of the methods as it would apply to their lives. A boy gave one for inductive reasoning. He said when he goes for ice cream he is accustomed to purchasing chocolate ice cream and always associated the colour brown as a chocolate flavour (observation). Thus, he was of the view that all brown coloured ice-cream was chocolate (conclusion). However, when he went for ice-cream on another occasion, he chose the brown coloured ice-cream with the perception that it was chocolate but in reality it was a peanut butter flavoured ice-cream (exception). This one example taught me an important lesson that I can apply to both my current and future life. The lesson was that in life we may make many observations, either of people or of a circumstance, and form opinions based on these observations, but sometimes our observations can lead us to a false opinion. In my opinion, inductive reasoning has been more useful in science. This is because it allows for science to grow as there would always be the possibility of observing new things thus enabling scientists to create new theories or laws.
Whereas, deductive reasoning is based on inductive reasoning. It uses the generalizations from observations and apply it to a specific case, thus it does not further science. However, I think deductive reasoning plays a vital role in the accuracy of scientific claims as once the general statement being used is true, the deduction should be correct. On the contrary, with inductive statements there is always an element of uncertainty. Hypothetico-deductive method stresses on the idea of falsification. It is where a hypothesis is proposed, and consequences are deduced, which are then tested against experience. If the hypothesis is falsified, then we learn from the attempt, and are in a position to produce a better one. If not, then we can try other tests.
I began to appreciate the use of these terms when I was able to apply them to my line of study. Initially, I was of the view that that law had no relationship with science and I was very pleasantly surprised when I realized that law employs both inductive and deductive reasoning. Case law principles are created by inductive generalization and the relevant legal principles are applied to the facts of a particular case by deduction.
