I cannot know

USAGE SUMMARY

The phrase "I cannot know" is correct and usable in written English.
You can use it to express that you lack the ability to know something. For example: "I cannot know how to fix this problem."

✓ Grammatically correct

Science

News & Media

Encyclopedias

Human-verified examples from authoritative sources

Exact Expressions

44 human-written examples

If I am to know a syllable SO, and that syllable is no more than its elements, then I cannot know the syllable SO without also knowing its elements S and O. Indeed, it seems that coming to know the parts S and O is both necessary and sufficient for coming to know the syllable SO.

SEP

Because knowing one thing is a precondition for knowing the other, and vice versa, I cannot know either of them.

SEP

I cannot know.

The New York Times

I cannot know for sure.

The New York Times

These are things I cannot know.

The New York Times

How fair or typical that is, I cannot know.

The Guardian

Human-verified similar examples from authoritative sources

Similar Expressions

14 human-written examples

Even if I lose my way and cannot know which road I should take, all I have to do is to take my mobile phone from my pocket.

Language Testing in Asia

I submit that we cannot know this, we can only guess.

Huffington Post

We cannot know, and I shudder to think, how deeply these influences have conditioned public consciousness.

The Guardian - Opinion

You cannot know what I know.

Huffington Post

I know I cannot love fully.

Huffington Post

Expert writing Tips

Best practice

When using "I cannot know", consider adding a qualifying phrase to explain the reason for your lack of knowledge, such as "I cannot know for sure" or "I cannot know the full extent of..."

Common error

While "I cannot know" is a valid expression, overuse can make your writing sound repetitive. Vary your language by using synonyms like "I am unsure", "I have no way of knowing", or "I am uncertain".

Linguistic Context

The phrase "I cannot know" functions as a declarative statement expressing a lack of knowledge or certainty. This is supported by Ludwig's examples, where the phrase is used to convey a speaker's inability to confirm or determine something. The phrase highlights a limit in one's understanding or access to information.

Expression frequency: Common

Frequent in

News & Media

52%

Science

32%

Encyclopedias

4%

Less common in

Wiki

2%

Formal & Business

0%

Social Media

0%

Ludwig's WRAP-UP

In summary, the phrase "I cannot know" is a grammatically correct and common way to express a lack of knowledge or certainty. As confirmed by Ludwig, it is used in various contexts, ranging from news and media to scientific discussions. While versatile, varying your language and considering synonyms can help prevent repetition in writing. The phrase is generally neutral in register and serves primarily to acknowledge the limits of one's understanding. It's more nuanced than "I don't know", implying a deeper inability to ascertain information.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

I cannot say for sure

Limits the scope of knowledge, indicating uncertainty about a specific claim.

I have no way of knowing

Focuses on the lack of means or method to acquire knowledge.

I cannot be certain

Indicates a lack of sureness or conviction about something.

I am unable to ascertain

Replaces "know" with a more formal synonym, "ascertain", suggesting a difficulty in determining something definitively.

I lack the knowledge

Directly states the absence of required information or understanding.

I am not able to determine

Emphasizes the inability to reach a conclusion or decision.

It is impossible for me to know

Highlights the impossibility of knowing, adding a sense of finality.

I am in the dark about

Uses an idiomatic expression to convey a complete lack of knowledge.

I haven't any idea

An informal way of expressing a complete lack of knowledge about something.

It's beyond my comprehension

Highlights that the topic is too complex to understand.

FAQs

How can I rephrase "I cannot know" to sound more formal?

For a more formal tone, consider using phrases like "I am unable to ascertain", "I am not in a position to know", or "It is not possible for me to determine". These options provide a similar meaning while conveying a higher level of formality.

What's a more casual way to say "I cannot know"?

Informal alternatives include "I have no idea", "I can't say for sure", or "Your guess is as good as mine". These options are suitable for everyday conversations and less formal writing.

Is "I cannot know" always interchangeable with "I do not know"?

While similar, "I cannot know" often implies a deeper limitation on your ability to know something, whereas "I do not know" is a more general statement of ignorance. Consider the subtle difference when choosing between the two.

What can I say instead of "I cannot know how"?

Alternatives for "I cannot know how" include "I'm unsure how", "I don't know how", or "I haven't a clue how". You might also use phrases like "I'm uncertain as to how" depending on the context.