Logos: Data and Evidence
Support arguments with concrete statistics, research findings, and measurable facts.
What & why
Specific numbers and named sources signal that a claim has been checked, which tends to raise the speaker's perceived credibility and lower the listener's uncertainty. Precise figures also act as anchors: once a concrete value is in mind, it shapes how people judge what follows. Quantified evidence gives the rational, skeptical part of an audience something to grip, making a position feel earned rather than asserted. The effect depends on the source seeming trustworthy, since a number from a doubtful origin can backfire and invite scrutiny.
Before & after
“Studies show this works better.”
“A/B testing with 50,000 users showed the new design increased conversions by 23% with 99% statistical confidence.”
When you’ll use it
Business cases and ROI justifications
Performance reviews with quantified achievements
Research presentations and data analysis
Sales presentations requiring proof of value
Pro tip
Use specific numbers, sample sizes, and confidence levels when citing data.
Questions & answers
What is logos through data and evidence in presentations?
How do I present data effectively in business presentations?
What makes data and evidence credible to business audiences?
Learn more
Practice this concept
Practice persuasive speaking
Apply rhetorical appeals in your own speech and get AI feedback on credibility, emotional resonance, and logic.