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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
i think therefore
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "i think therefore" is not correct as it should be capitalized as "I think therefore." It can be used in discussions about philosophy or reasoning, often as a lead-in to the conclusion that follows.
Example: "I think therefore I am, which suggests that the act of thinking is proof of one's existence."
News & Media
Science
Encyclopedias
Alternative expressions(19)
thus I conclude
Thus, I conclude
cogito ergo sum
the cogito
I think therefore I am
self-awareness
to think is to be
To think is to be
My thoughts define my existence
Thinking is proof of my being
I think therefore I doubt
I think therefore I pray
I write therefore I am
I think therefore I Do
I think therefore I go
proof of existence
thinking being
introspection
emotional intelligence
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
59 human-written examples
It was this thinking that led Descartes to proclaim: "I think, therefore I am".
News & Media
I think, therefore I doubt.
News & Media
"I think, therefore I am".
News & Media
"I think, therefore I am": O.K.
News & Media
"You know: 'Cogito, ergo sum.' I think, therefore I am".
News & Media
"I think therefore I am undermining myself," said Descartes' sister.
News & Media
I Think, Therefore I Shop Museum for Applied Art, Frankfurt.
News & Media
Is it true that "I think, therefore I feel"?
News & Media
I think therefore he won't be very sympathetic".
News & Media
On Mr. Jensen's backpack was a button with the words, "I think, therefore I'm dangerous".
News & Media
Discarding everything he wasn't certain of He said 'I think therefore I am a rhubarb tart'.
News & Media
Expert writing Tips
Best practice
Use "I think therefore" to introduce a logical conclusion, ensuring the "I think" portion reflects genuine contemplation, not mere opinion.
Common error
Avoid using "I think therefore" as a conversational filler. Ensure it introduces a conclusion genuinely derived from preceding thought, not just a weak assertion.
Source & Trust
85%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "I think therefore" functions as a discourse marker, explicitly signaling a connection between a stated premise and the subsequent conclusion. It is commonly used to introduce a logical inference based on one's own reasoning. As Ludwig suggests, the phrase is widely used even though it may not be grammatically correct in every context.
Frequent in
News & Media
45%
Science
25%
Encyclopedias
10%
Less common in
Formal & Business
5%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, the phrase "I think therefore" is a common way to introduce a conclusion based on personal reasoning. While it may not always be grammatically perfect, its widespread usage across diverse sources such as news, science, and encyclopedias makes it acceptable in many contexts. Ludwig highlights that it functions as a discourse marker, signaling a logical inference. However, it's essential to ensure that the phrase is used to introduce a genuine conclusion, rather than just as a filler. For more formal or objective contexts, alternatives like "hence, I conclude" or using "therefore" alone, may be more appropriate.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
Therefore, my view is
Directly states a personal view derived from a preceding thought.
Hence, I conclude
Suggests a formal deduction; a conclusion based on evidence.
From this, I gather
Suggests collecting and understanding information that leads to a conclusion.
Thus, I reason
Highlights the reasoning process leading to a statement.
Based on this, I determine
Suggests a firm determination after considering the evidence.
Consequently, I believe
Emphasizes a belief that arises as a result; a consequence.
For this reason, I deem
Formal way to express judgment based on a stated reason.
Accordingly, I infer
Indicates an inference drawn from given information.
It follows that I consider
Implies a logical consequence leading to a consideration.
In light of this, I surmise
Indicates a guess or conjecture based on available information.
FAQs
How can I use "I think therefore" in a sentence?
Use "I think therefore" to connect a premise or observation to a logical conclusion. For example: "I have studied the data, I think therefore I can make an informed decision."
What's a more formal alternative to "I think therefore"?
For a more formal tone, consider using phrases like "hence, I conclude", or "thus, I reason", which emphasize a logical deduction based on evidence.
Is it always necessary to include 'I think' before 'therefore'?
No, using "therefore" alone is often sufficient and can sound less repetitive. The "I think" emphasizes personal reasoning, but it's not grammatically required for the sentence to make sense.
How does "I think therefore" differ from simply using 'therefore'?
Adding "I think" highlights the subjective nature of the conclusion, indicating it's based on personal reasoning or belief. Using 'therefore' alone implies a more objective, logical consequence.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
85%
Authority and reliability
4.1/5
Expert rating
Real-world application tested