The standard logos definition in writing classes is persuasion by logic: convincing an audience with facts, evidence, clear reasoning and sound examples. When an essay argues for a later school start by citing sleep research and attendance figures, it is using logos.
The word is Greek, and it has a much longer history than the essay classroom. In ancient Greek, logos could mean word, speech, account, reason or argument. Philosophers used it for the rational order behind the world, and Christian writers used it for the divine Word described at the opening of the Gospel of John. This page covers all three uses, starting with the one students meet most.
Entry at a glance
Meaning
Appeal to logic and evidence; in Greek, word or reasonPart of speech
Noun; plural logoiPronunciation
LOH-gohs (US also LOH-gahs)Origin
Greek logos, from legein (to speak, to gather)Partners
Related words
logic, logical, and the ending -logy as in biologyFields
Rhetoric, philosophy, theology
Logos definition in rhetoric
In his treatise on rhetoric, Aristotle described three ways a speaker persuades. Ethos relies on the speaker's credibility, pathos on the audience's feelings, and logos on the argument itself: the proof offered in the words. A speech strong in logos leaves listeners thinking, that follows.
Logos tools include:
- statistics and data from reliable sources
- facts and documented examples
- cause and effect reasoning
- analogies that make a point easier to grasp
- answering counterarguments step by step
Good writers usually blend all three appeals. A purely logical argument can feel cold, and a purely emotional one can feel manipulative. For the wider art, see rhetoric.
Spotting logos: worked examples
- A city council member argues that a new bus lane cut average commute times by twelve minutes in a trial month, so it should be made permanent.
- A student essay claims a four-day school week saves money, then shows the district's spending on heating and transport per day.
- A product review compares battery life measured over five tests rather than relying on the reviewer's impression.
- A doctor explains that a vaccine schedule works because each dose builds on the immune response of the last.
When logos goes wrong
An argument can look logical while hiding errors. Watch for:
- Cherry picking: using only the numbers that support your side.
- False cause: assuming that because B followed A, A caused B.
- Hasty generalisation: one or two cases presented as a rule.
- Weak sources: figures with no clear origin.
In an essay analysis, you can say a writer's logos is strong if the evidence is relevant, sufficient and fairly presented, and weak if the reasoning has gaps. Logos is about the quality of the inference, not just the presence of numbers.
Logos in Greek philosophy
Early Greek thinkers, notably Heraclitus, used logos for an underlying order or rational principle that governs how the world changes. Later the Stoic philosophers taught that this logos runs through all of nature, and that living well means living in agreement with it. In this sense logos is less about speeches and more about the reason built into reality. That idea fed into the English word logic, and into the ending -logy, meaning the study or account of something, as in psychology and anthropology.
Logos in Christian theology
The Gospel of John, written in Greek, opens by speaking of the Word that was with God in the beginning, and the Greek term there is logos. Christian tradition understands this Word as the eternal Son of God, identified with Jesus, through whom creation came about and who became human. Theologians therefore speak of the Logos, capitalised, as a title. Other religious traditions do not share this reading, and scholars discuss how far John's use connects with earlier Greek and Jewish ideas about divine wisdom and the word of God. More on related ideas appears in our guide to faith terms.
Logos, logic and logos as a plural
| Form | What it means |
|---|---|
| logos (Greek term) | Logical appeal, or reason or word; plural logoi |
| the Logos | In Christian theology, the divine Word |
| logic | The study and rules of correct reasoning |
| logos (plural of logo) | Company symbols; a different English word, though related through Greek |
Context tells you which one you have. In an English literature or debate class, it is almost always the appeal to reason. Our writing and grammar hub covers more classroom terms like this one.
Frequently asked questions
How would a teacher give a quick logos definition?
Logos means persuading with logic: facts, data, examples and reasoning that lead an audience to a conclusion. It is one of the three classic appeals, with ethos and pathos.
What is an example of logos?
Arguing that a city should plant more trees because shaded streets measured several degrees cooler in summer is logos. The claim rests on evidence and a clear chain of reasoning.
How is logos different from pathos?
Logos persuades through reason and proof, whereas pathos works on feelings like hope, fear or sympathy. Strong arguments often use both, carefully.
How do you pronounce logos?
Say LOH-gohs, two syllables, leaning on the first. Many Americans say LOH-gahs instead, and teachers accept either.
Where does Logos appear in the Bible?
In the Gospel of John, Logos is the Greek word translated as Word. Christians understand it as a title for Jesus as the eternal Word of God.
What is the plural of logos?
As a Greek term, the plural is logoi, mostly used by scholars. In everyday English, logos is also simply the plural of logo, which is a different word.