What Is Logos? | Definition, Meaning & Examples

Logos is an appeal to an audience’s sense of logic and rationality and usually involves objective facts and figures. With the use of solid evidence, the speaker or writer can support their argument and persuade their audience or readers.

Logos example
Because firearms are potentially lethal, only responsible, mature, and trained individuals should be permitted to own and handle them. Therefore, children, lacking maturity and understanding, should not have access to firearms.

“Logos” is a term mostly used in persuasive speaking and writing, including political speeches, marketing, and legal arguments.

Logos definition

Logos (or appeal to logic) is a mode of persuasion employed to support an opinion, argument, or conclusion by appealing to an audience’s intellect. Logos means “order,” “word,” or “reason” and the term “logic” is derived from it.

When an author or speaker appeals to logos, it means they are using facts, statistics, relevant examples, or any other form of proof appropriate to the topic. Additionally, they draw clear and logical connections between ideas.

Appeal to logic is effective only if the audience accepts the premises. In the example above, logos works only if the audience agrees that children lack maturity or that only trained individuals should handle firearms. If someone in the audience disagrees with that, they will simply reject the argument. Providing evidence, such as statistics about accidents involving children and firearms, can help the audience to accept the logical argument.

Ethos, logos, pathos

Logos, together with ethos and pathos, is one of the three basic modes of persuasion in rhetoric according to Aristotle, the ancient Greek philosopher. The purpose of rhetoric was to discover the means of persuasion in an argument. This can be achieved through:

  • Ethos (the character of the speaker/writer): When someone appeals to ethos, they are trying to make an audience trust them so that they will accept their argument. This involves tapping into the audience’s values and beliefs and showcasing knowledge and expertise in the subject at hand.
  • Logos (the argument itself): A logical appeal is rational support of an argument through a well-organized line of reasoning. This involves evidence, cause-and-effect thinking, examples, or comparisons to support one’s position and persuade an audience.
  • Pathos (the emotional state of the audience): A writer or speaker using emotional appeals is trying to make an audience feel something: sorrow, anger, pride, etc. Building an empathetic bond will make the audience more likely to agree with the argument.
Not every argument needs to incorporate all three rhetorical appeals. It is important to consider the context and subject at hand to determine the best combination of appeals to use.

Also, using rhetorical appeals does not necessarily imply that we should accept the argument at face value. Sometimes appeals to logic persuade people by merely appearing to prove something. Speakers, for example, may misrepresent an issue by quoting scientific studies that agree with their viewpoint. By doing so, their argument seems credible, whereas they argue for something untrue. These types of arguments are called logical fallacies.

Logical appeals

Logos rests mainly on two types of logical reasoning:

Inductive reasoning

In an inductive argument, the speaker or writer starts from specific examples or observations and forms a broad generalization that is meant to apply to all cases.

Inductive reasoning example
“Every time you eat peanuts, you start to cough. Therefore, you must be allergic to peanuts.”

Keep in mind that the conclusion is never certain in this type of reasoning and can only be expressed as a probability. If the number of examples or observations is not sufficient or representative, the conclusion may lead to a hasty generalization fallacy.

Deductive reasoning

In a deductive argument, the speaker or writer starts from a general principle, law, or statement that is assumed to be true and arrives at a specific conclusion.

Deductive reasoning example
“What goes up, must go down. Therefore, if I throw this ball into the air, it will go down.”

The conclusions drawn from deductive reasoning are considered certain if the premises are true and the logical structure of the argument is valid. However, if the logical structure is flawed or the premises are incorrect, it can lead to fallacies like the non sequitur fallacy or denying the antecedent.

In short, inductive reasoning moves from the specific to the general, whereas deductive reasoning moves from the general to the specific.

Logos examples

Appeal to logos is used in many contexts, such as advertising and literature.

Logos in advertising

Advertisements employing logos try to persuade consumers by presenting rational evidence that supports the decision to purchase the advertised product or service.

Logos example in advertising
Logical appeals in advertising include the citation of facts, product characteristics, pricing information, statistics, etc. On screen, this could translate as:

  • A car commercial enumerating all the new safety features of the latest edition.
  • A yogurt commercial highlighting the health benefits of eating a high protein, low sugar breakfast.
  • A telecom provider commercial shows a map with coverage statistics while the voice-over explains the technical specs and pricing.

Logos in history

In the Declaration of Independence, Thomas Jefferson employs logos to justify the American colonies’ decision to separate from Great Britain. In the following excerpt, logos is used in the list of grievances against the King.

Logos example in the Declaration of Independence
[…] The history of the present King of Great Britain is a history of repeated injuries and usurpations, all having in direct object the establishment of an absolute Tyranny over these States. To prove this, let Facts be submitted to a candid world.

He has refused his Assent to Laws, the most wholesome and necessary for the public good.

He has forbidden his Governors to pass Laws of immediate and pressing importance, unless suspended in their operation till his Assent should be obtained; and when so suspended, he has utterly neglected to attend to them. […]

Logos in literature

In Shakespeare’s Othello, Iago manipulates the main character into believing his wife Desdemona is unfaithful, stirring his jealousy. Although Iago is speaking out of spite, he often uses logical reasoning to conceal his intentions.

Logos example in literature
In this passage from Othello (Act 3, Scene 3) Iago presents evidence that Desdemona is capable of deception and subtly urges Othello to connect the dots.

IAGO: She did deceive her father, marrying you,
And when she seemed to shake and fear your looks,
She loved them most.

OTHELLO: And so she did.

IAGO: Why, go to, then!
She that, so young, could give out such a seeming,
To seel her father’s eyes up close as oak,
He thought ’twas witchcraft! But I am much to

Frequently asked questions about logos

How do you identify logos in an argument?

You can identify logos in an argument by asking yourself the following questions:

  • Does the writer or speaker use facts, statistics, or reasoned analysis to support their claim?
  • Is the argument well-organized, with one idea logically following the next one?
  • Does the writer or speaker include opposing arguments and try to refute them with evidence?
  • Is the reasoning transparent and free from ambiguity?
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Kassiani Nikolopoulou, MSc

Kassiani has an academic background in Communication, Bioeconomy and Circular Economy. As a former journalist she enjoys turning complex information into easily accessible articles to help others.