Blog 4- Essay

 Deductive Arguments and Reasoning

Knowledge and truth are big factors in philosophy, especially when it comes to deductive arguments and reasoning. A deductive argument can be defined as, “the presentation of statements that are assumed or known to be true as premises for a conclusion that necessarily follow from those statements” (Techtarget). When it comes to deductive arguments, they must be sound and valid. Validity of an argument depends on how the premises are related to the conclusion. They have to complement each other to the point where if the premises are true, then the conclusion must be true. “Logic can help us determine whether an argument is valid, but logic alone cannot establish whether an argument is sound.” (Ultimate Questions CH3, 42). In order for an argument to be sound, it must first be valid, and secondly we must know it to be true. This theory of knowledge is referred to as epistemology. There are four main, well-known valid argument forms which can be classified as deductive arguments. These include Modus Ponens, Modus Tollens, Disjunctive Syllogism, and Hypothetical Syllogism. The two that I want to focus on are Modus Ponens and Modus Tollens.

The first of these four argument forms is Modus Ponens. This comes from Latin, translating to “method of affirming”. When utilizing this method of argument, you can come to a logical conclusion based on inference. From Ultimate Questions Chapter 2, an example of Modus Ponens is “ 1. If P, then Q; 2. P; Therefore:Q”. This directly states that if P is true, then Q is also true, so when P is listed, Q must be true. An example of this could be 1. If it is dark outside, then it is nighttime; 2. It is dark outside; Therefore: It is nighttime.

The next argument form is Modus Tollens. This also comes from Latin and is the opposite of Modus Ponens. Modus Tollens directly translates to “ method for denying”. This is a way to prove that something is not right. When the proposition and the antecedent are dependent on each other, and the proposition is denied, the antecedent will also be denied. An example of this could be 1. If it is dark outside, then it is nighttime; 2. It is not dark outside; Therefore: It is not nighttime. 

I think that deductive reasoning and argumentation is the better way to face an argument. My plan after college is to go to law school and become an attorney. Lawyers focus on facts and use deductive reasoning constantly. In professions like law, inductive reasoning can still be used in some circumstances, but very rarely. Cases need to be indubitable, or without a doubt, and deductive arguments use logic and facts to come to a conclusion, while inductive reasoning uses probability, therefore deductive reasoning is a better fit for lawyers. Inductive reasoning can be better utilized in other professions, like science. A scientist would make an observation and then create a hypothesis based on said observation. These observations and hypotheses help expand their knowledge and view of the world. 

In my current life, I use deductive reasoning constantly throughout my day. If I work an extra shift, then I will make more money; I work an extra shift; Therefore: I make more money. If I don’t get out of bed, I won’t make it to class; If I don’t make it to class, then I won’t learn the material for the test: Therefore: if I don’t get out of bed, then I won’t learn the material for the test. 

Even the smallest decisions we make utilize deductive reasoning. That could be about whether you should get out of bed in the morning, saving time by not making your bed, deciding to save money by making breakfast in your apartment instead of buying fast food, choosing to do your homework so you can keep your grades high, and many others. As humans, we learn by making connections and comparisons; when we are able to relate things, we are able to learn more about them.

Works Cited:

Contributor, TechTarget. “What Is Deductive Argument? - Definition from Whatis.com.” WhatIs.com, TechTarget, 27 Feb. 2017, https://www.techtarget.com/whatis/definition/deductive-argument. 

Rauhut, Nils Ch. “Chapter Two: Philosophical Tools.” Ultimate Questions Thinking about Philosophy, Pearson, Hoboken, 2019. 

Rauhut, Nils Ch. “Chapter Three: What Do We Know?.” Ultimate Questions Thinking about Philosophy, Pearson, Hoboken, 2019.