Deductive Versus Inductive Reasoning

Compare and Contrast the Inductive and Deductive Research Paradigm/Approaches When underlying assumptions and intellectual structure are built upon research, observation, or development in a field of inquiry a paradigm is created. The way we perceive the world around us or the way facts and theories are established are generated in different ways. Knowledge is constantly being produced, based on assumptions or reasoning. One might see a story in the news of a shark in Southern California that attacks a surfer.

A new acquired knowledge or hypothesis may arise that all Southern California sharks attack people. Is generating such a hypothesis a valid reasoning? Or if we flip it — one could deduct from the generalized fact that if all apples are fruit and all fruits grow on trees, then all apples grow on trees. But is this hypothesis valid? How do we go about testing or generating hypotheses about different topics? On a scientific level, knowledge and hypotheses are forever being generated or tested.

One might hypothesize that “the color of a mineral is determined by its crystal structure. ” How could this hypothesis be tested? Through deductive reasoning, this can be done — for the purpose of deductive reasoning is to test a hypothesis. Finding other examples to attempt to prove or disprove this hypothesis is the beginning step to reasoning out this hypothesis. If the color of a mineral is determined by its crystal structure, then all purple minerals should have the same crystal structure.

However, with the power of observation, it is known that a purple amethyst has a hexagonal structure and purple fluorite has an isometric structure. By observing crystals that do not fit this hypothesis, it can be deducted that this hypothesis (“the color of a mineral is determined by its crystal structure”) is not supported based on the known facts of the other crystals’ shapes in relation to their color. Making deductions is the key component when a cause cannot be directly observed, and only consequences can be observed.

This type of strategy to testing a hypothesis is deductive reasoning; it is a top down approach to reasoning, where one starts with a general case and deduces specific instances, which is also known as generalizing. Deductive reasoning involves making conclusions based on previously known facts. In the instant of the crystals, the generalization end up being invalid. However, an example of a more valid generalization would be if gravity makes things fall, then the apple that hit my head was due to gravity.

Using a scenically-induced hypothesis like such, gravity as the cause is able to be tested. Deductive reasoning is based on a more objective scientific reasoning. An etic perspective is the driving force behind reaching such an hypothesis. An etic perspective is a view from an outsider looking in; this outsider or observer makes objective generalizations by scientifically observing and deducing using multiple variables or facts to test a theory. Valid deductions are best produced by experts in a particular subject or field of study.

For example, a biologist versus a undergraduate biology student would most likely make better deductions about a crystal’s color in relation to its structure, because the expert is more knowledgeable in that field and can make more valid deductions to test a generalization. Deductive reasoning is a very effective strategy and effective when the premises are correct and each step in the process of deductive reasoning follows logically from the previous step. Premises used in deductive reasoning are very important.

Hypotheses are also generated by taking specific instances or experiences and creating a general principle based on inductive reasoning. For example, a geometry student might measure the interior angles of a group of randomly drawn triangles. He or she determines that the sum of the three angles is 180° regardless of the triangle. It would be very tempting to make an assumption about the sum of the interior angles of a triangle. Putting together each separate fact provides evidence to support a general statement about the interior angles which results in the inductive reasoning that all triangles are made up of 180°.

Rather than using observations and making deductions (general to specific) like with deductive reasoning, many people collect relevant characteristics and attempt to construct bigger principles from it (specific to general) using inductive reasoning. This unique creative, out-the-box thinking is also very effective in generating a valid hypothesis. Inducing broader knowledge based on set of obervations or experience can be very valuable because it allows us to form ideas about groups of things in real life or scientifically leads to a more careful study of a particular subject.

However, such reasoning stems from an emic perspective, one that is subjective, looking from the inside out. And many times a subjective, closed-in reasoning process can result in a hypothesis that is skewed. Just because a person observes a number of situations in which a pattern exists does not necessarily mean that that pattern is true for all situations. It is not always the most valid method of proof. Invalid inductions can many times result in stereotypes, which skew reality due to limited perception or false creation.

With inductive reasoning, the purpose of using the approach is to develop or generate a theory; and with this approach it can be much more open to question for the conclusion that is produced because it is a bigger bag than the evidence on which it is based. Both inductive reasoning and deductive reasoning can result in a skewed hypothesis due to the inability to test every variable. However, after continuous testing and research hypotheses can be scientifically proven. Both inductive and deductive reasoning are used in every day life and in the scientific world and help humankind make sense or make facts of the world around them.