Be Certain, Not Opinionated
In SEO content writing, precision and certainty are what build trust and authority. Based on Koray Tuğberk Gübür's methodology, this guide explains how a statement moves from a vague personal opinion to a well-supported fact — and how that shift affects content performance in search results and AI Overviews.
Introduction
Precision and certainty are among the most important factors that determine content quality today, especially as search engines and AI systems increasingly rely on understanding information and extracting facts from it.
Content is no longer just about using the right keywords — the goal now is to deliver information that is clear, precise, and verifiable. The more content is grounded in documented facts, the more readers trust it, and the easier it becomes for Google and AI systems to understand it and cite it in search results and AI Overviews.
That is why Koray Tuğberk Gübür stresses that a writer should express a degree of certainty that matches the strength of the evidence, and should avoid statements built on unsupported opinions or predictions.
What does the "Be Certain" rule mean?
This rule means basing your writing on confirmed information and verifiable facts, and avoiding turning your personal opinions or predictions into stated facts.
Every claim you write should be clear, precise, and backed by evidence whenever that is necessary.
A professional writer doesn't write what they believe — they write what can be proven.
Why does this rule matter for SEO and AI?
Applying this rule delivers several important benefits:
Builds trust and authority
When readers find precise, evidence-backed information, their trust in the content and the site grows, strengthening the site's authority in its field.
Improves how search engines understand content
Google and AI systems rely on extracting facts from pages. The clearer and less ambiguous the sentences, the easier the content is to understand and classify.
Increases visibility in AI Overviews
AI systems favor content that offers confirmed, verifiable information over content filled with opinions or vague generalities.
Improves the user experience
Readers are looking for a clear answer, not predictions or generic advice. The more direct and precise the information, the more useful and easier to understand it becomes.
Why avoid opinion-based statements?
Statements that contain words like "should," "must," "it's better to," "we need to," or "will" express a personal viewpoint or a general recommendation — not a proven fact. This kind of phrasing weakens the credibility of the text and confuses algorithms that are looking for precise, clear information.
⚠️ A note of caution
Not every word like "must" or "should" is wrong. If the statement is based on evidence or an official recommendation, using it is entirely correct.
Example:
This isn't a matter of opinion — it's a mandated procedure within medical protocols.
So the problem isn't the word itself — it's an unsupported claim.
The sun will rise tomorrow — an indirect predictive statement.
The sun rises every day — a stable, certain statement.
You should drink more water.
Drinking water is essential for hydration.
How do we turn opinion into fact?
Three examples showing how phrasing shifts from a vague personal directive into a confirmed, credible statement:
| Type | Original phrasing | Problem | Improved phrasing |
|---|---|---|---|
| Opinion | You should exercise regularly | Personal directive, unsupported | Regular exercise improves cardiovascular health |
| Opinion | It's better to drink water daily | Imprecise, lacks a reference | Drinking water is essential for hydration |
| Vague | You'll likely see results within a week | Vague, predictive | Studies show treatment results often appear after one week of use |
Google prioritizes certain, precise content within AI Overviews and AI-driven results — ambiguity weakens visibility, and certainty raises it.
Editorial benefits of using certain statements
Builds trust and authority
Content built on precise facts strengthens reader trust and positions the site and writer as a reliable reference.
Improves search engine performance
Search engines favor trustworthy, certain content, increasing its chances of ranking higher in search results.
Increases engagement and sharing
Users engage more with content they find trustworthy, which raises click-through rates, time on page, and social sharing.
How does a writer apply this rule?
Verify every fact
Cross-check every fact against reputable sources before including it in your content. Citing authoritative sources further strengthens credibility.
Replace directive phrasing with precise language
Instead of "you should drink water," write "drinking water is essential for kidney function and circulation" — a specific, evidence-based outcome.
Avoid ambiguity
Remove phrases open to multiple interpretations, such as "maybe," "might," or "it's recommended," and replace them with proven results or clear statistics.
Match your degree of certainty to the strength of the evidence
If there is only a single study, don't write "this fact is certain" — write "a study showed that...". If the information is scientifically established, it can be stated directly.
Applied comparison for the same query
When phrasing an answer to a search query, the difference between certain and weaker phrasing becomes obvious:
| Query | Best answer | Less effective answer |
|---|---|---|
| Why should you drink water? | Drinking water is essential for hydration and supports vital processes such as digestion and circulation. | It's better to drink water daily to stay healthy. |
| Is exercise good for the heart? | Regular exercise reduces the risk of heart disease by up to 30%. | Exercise is recommended because it's good for the heart. |
| Is investing in cryptocurrency successful? | According to financial reports, cryptocurrencies have delivered high returns over the past decade. | Investing in cryptocurrency can yield high returns. |
Full guide: vague phrases vs. certain alternatives
The table below is a quick reference to use while editing and reviewing:
| Type | Original phrase | Why it doesn't work | Certain alternative |
|---|---|---|---|
| Vague | It might be useful | Imprecise, expresses a possibility | Studies have shown its benefit in... |
| Opinion | You have to | Personal directive, doesn't reflect a general fact | It is recommended for treating... per the [Medical Association] |
| Vague | You'll probably see improvement | A vague, predictive phrase | Clear results appeared in 80% of patients within two weeks |
| Opinion | The best option is always | Inaccurate generalization, lacks context | The best option depends on each person's health condition |
| Vague | It is believed that | Based on an undocumented assumption | According to research published in [source name]... |
| Opinion | You should consume more of... | Direct instruction without evidence | Dietary guidelines show the recommended daily amount is... |
| Vague | Some people prefer | Imprecise, doesn't specify the share or who they are | 65% of survey respondents chose... |
| Opinion | It's indispensable | An overstated expression, unsuitable for scientific presentation | It is widely used to treat cases of... |
| Vague | It is said that | An unreliable, untraceable formulation | The World Health Organization has confirmed that... |
| Opinion | It is imperative to | A mandatory style that reflects no source or reference | It is advised within the medical protocols for... |
Conclusion
The "Be Certain" rule means that all the information you present is precise, clear, and supported by evidence whenever possible.
A professional writer doesn't write what they assume to be true — they write what they can prove, using a degree of certainty proportional to the strength of the available evidence. This is one of the key reasons content becomes more trustworthy to readers, and easier for Google and AI systems to understand and cite.
