Uncovering Valid Deductive Argument: A Guide for Students
21.04.2023

Uncovering Valid Deductive Argument: A Guide for Students

Arguing effectively is an essential skill, but not all arguments are equal, and they often vary power. Since some arguments are stronger than others, knowing what aspects make reasoning stronger can help you express your thoughts convincingly. This article will review what valid deductive arguments are, suggest examples of both deductive and inductive reasoning and claims for their complete understanding, and provide some tips how to develop and improve your reasoning skills.

Different Argument Types

Before we jump into deductive arguments, let’s differentiate between the two types: deductive and inductive.
  • Deductive arguments are like puzzles. They are based on the idea that the conclusion follows logically from the premises. If the starting points are true, the ending picture must also be true. Deductive reasoning is used in math, philosophy, and other areas that require exact and logical thinking.
  • Inductive arguments, in contrast, rely on observation and evidence. They don’t provide absolute certainty, but they can still be persuasive. Inductive reasoning is used in science, social sciences, and fields dealing with real-world data.

Valid Deductive Argument: A Closer Look

A valid deductive argument is a well-reasoned claim where the conclusion has to derive logically from the premises if they’re true. An example of a logically strong and sound claim would be one where it is impossible for the premises to be true and the conclusion false. Evaluating the validity of a deductive argument involves checking if the initial premises are true. If they are, the conclusion will be true as well. Yet, if any premises are false, the conclusion can’t be logically deduced, which makes the reasoning invalid. Let’s examine a valid argument example to understand its logic:
  • Premise 1: All dogs have four legs.
  • Premise 2: Spot is a dog.
  • Conclusion: Thus, Spot has four legs.
This deductive argument can be considered valid because if we assume the premise to be true, the conclusion has to be true. There’s no scenario where the premises are true and the conclusion is false. To see the difference, let’s now have a look at an invalid argument:
  • Premise 1: All birds can swim.
  • Premise 2: A penguin is a bird.
  • Conclusion: Hence, a penguin can swim.
This claim does not hold water and, thus, is invalid because the first premise is false. Even though the second premise that a penguin is a bird is true, not all birds can swim. So, we can’t deduce the conclusion is logical and right because the first premise is false. In short, a valid deductive argument is one where the conclusion must logically follow from the true premises. It’s crucial to check the truth of the initial premises to determine if a claim holds water and can be treated as valid.

What is Strong Inductive Argument?

A strong inductive argument is one that provides evidence that makes the conclusion probable but not granted. This kind of reasoning is different from deductive, which assumes that the conclusion is true only if the premises are true. Let’s review an example of strong inductive arguments, which is given below:
  • Premise 1: Every crow we’ve seen is black.
  • Conclusion: Thus, all crows are black.
While it’s likely that all crows are black based on the evidence in the premise, there’s still a chance that some crows aren’t black and can be of another color. Inductive arguments depend on probabilities, and their conclusion can change if the statement is updated with new evidence in the premise. If anyone sees a non-black crow, this fact can weaken the inductive argument. Still, inductive claims and reasoning can be convincing and helpful even if they’re not necessarily guaranteed to be true.

Why Is Deductive Reasoning Stronger Than Inductive Reasoning?

Both deductive and inductive reasoning have pros and cons and are applied depending on the situation. Still, deductive reasoning is typically said to be stronger because it guarantees that the conclusion is true given that the premises are true. In contrast, inductive reasoning only provides strong support for the conclusion without ensuring its truth. In addition, evaluating deductive claims for validity is easier compared to inductive arguments. Let’s describe the difference between inductive and deductive reasoning in simple terms. Deductive reasoning has a more straightforward structure, making it simpler to determine if the premises adequately support the conclusion. Inductive reasoning, on the other hand, oftentimes needs more complex analysis or other methods to determine its strength.

What Makes a Deductive Argument Sound?

For a deductive argument to be sound, it must meet a few key criteria:

Validity

The first requirement for a sound deductive argument is validity. The claim has to be valid, meaning the conclusion should logically follow from the premises. If the premises are true and the logic is solid, the conclusion will be true as well.

Truth of the Premises

The second requirement for a sound deductive argument is that the premises must be true. The argument’s premises have to be true for the conclusion to be true. If any premise is false, the conclusion cannot be true, making the whole claim unsound and invalid.

Soundness

If an argument is both valid and has true premises, then it’s sound. A sound argument provides conclusive proof of its conclusion.

Tips on How to Improve Deductive Reasoning

To develop and master your skills in deductive reasoning, there are several aspects you should consider:

Practice

Practice makes perfect. The more you practice deductive reasoning, the more effective will you become in it. Use any chance to master reasoning skills in your daily life, for example, when solving certain issues or making choices.

Learn Logic

Since deductive reasoning is based on logic, understanding logical principles is of the utmost importance. Reading books or taking courses on logic will help you learn and understand it.

Use Examples

Examples can help you understand deductive reasoning more competently. Look for examples of valid deductive arguments and try to identify the premises, conclusion, and logic used.

Check Your Assumptions

Deductive reasoning requires true premises. Make sure you’re not making any false assumptions and avoid false premises when constructing your arguments.

Be Critical

Last but not least aspect in practicing deductive reasoning is ability to be critical of arguments of your own and others. You need to be able to identify flaws in logic and assumptions, and be ready to revise arguments if needed.

Conclusion

In conclusion, using a valid deductive argument to reason your claim is a powerful way to provide conclusive proof of a conclusion. If you start with true premises and use solid logic, you can come to conclusions that are true as well. While deductive reasoning is considered to be stronger than inductive reasoning, understanding both types of arguments help you make informed decisions and evaluate claims. Practicing both types of reasoning and being critical of our own claims will allow improving both deductive and inductive reasoning skills and become more advanced thinkers. However, don’t underestimate the role of reviewing good examples of reasoning in order to better understand and apply it in your daily life.