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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
the reason thereof
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase 'the reason thereof' is correct and usable in written English.
It is typically used when referring to a concept or event, where 'thereof' indicates that the reason being referred to is related to the preceding concept or event. For example, 'The project was unsuccessful, and the reason thereof was poor planning.'.
✓ Grammatically correct
Science
Academia
News & Media
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
2 human-written examples
We believe that the reason thereof is non-specific hydrophobic sorption of antibodies.
Science
In case a woman fails to be successfully contacted at the time of follow-up, the reason thereof will be noted in brief in the trial registry as well as further attempts to contact the woman.
Science
Human-verified similar examples from authoritative sources
Similar Expressions
58 human-written examples
There are conflicting arguments on the rapid decline in mortality and the reasons thereof.
Science
We will address below a number of issues that warrant further investigation and the reasons thereof are as follows.
It is therefore important to detect and document delays in immunization (and the reasons thereof) in conflict areas where health services may still be available to some extent.
Science
We could find only one study that specifically investigated the extent to which HIV patients looked for care outside their own clinic in case of illness and the reasons thereof.
Science
To this award the court added $8,500, with interest from March 17 , 1919 as the value of the three contracts at the time of their cancellation, and the loss sustained by the petitioner by reason thereof.
Academia
For if as he saith, every body hath a proper and naturall place of the owne; by reason thereof necessarily it must be, that the earth from all parts should tend toward the midst, and the water afterwards upon it, serving (by meanes of their weight and ponderosity) in stead of a foundation to other elements of a lighter substance.
Academia
The court below found that the value of the contracts at the time of their cancellation and the loss sustained by reason thereof was $8,500, and in its judgment included this amount as a separate item.
Academia
Civil seizures or forfeitures and injunctive proceedings commenced prior to the effective date of section 701 shall not be affected by the repeals or amendments made by such section, or abated by reason thereof.
Academia
L. 91 513 not to be affected or abated by reason thereof, see section 1103 of Pub.
Academia
Expert writing Tips
Best practice
Use "the reason thereof" in formal writing where a slightly elevated tone is appropriate. Be mindful that it can sound archaic in modern conversation.
Common error
Avoid using "the reason thereof" in informal contexts. It can sound stilted or pretentious in casual conversation or less formal writing. Consider more direct alternatives like "the reason for that" or "why that happened".
Source & Trust
84%
Authority and reliability
4.2/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "the reason thereof" acts as a noun phrase functioning as a subject complement or appositive. It identifies or explains a previously mentioned subject, as Ludwig AI confirms with its analysis of various contexts.
Frequent in
Science
30%
Academia
25%
News & Media
20%
Less common in
Formal & Business
15%
Wiki
5%
Reference
5%
Ludwig's WRAP-UP
In summary, "the reason thereof" is a grammatically sound but formal phrase used to provide an explanation or justification, confirmed by Ludwig AI. Its formality makes it suitable for academic, scientific, or legal contexts, while less appropriate for casual conversation. More common alternatives include "the reason for that" or "why that happened". While examples are somewhat rare, source quality is high, primarily drawn from science, academia and news outlets.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
the cause of that
Replaces 'reason' with 'cause' and uses a more direct phrasing than 'thereof'.
the explanation for that
Substitutes 'reason' with 'explanation', offering a slightly more detailed sense.
the grounds for it
Uses 'grounds' in place of 'reason', indicating a justification or basis.
the rationale behind it
Emphasizes the logical basis or underlying principle.
the basis for that
Similar to 'grounds', but focuses on the foundational aspect.
the motivation for that
Highlights the driving force or incentive.
the purpose of that
Focuses on the intended outcome or aim.
the origin of that
Points to the initial source or beginning.
why that happened
A more direct and informal way of asking or stating the reason.
the upshot of that
Suggests the result or consequence, implying the reason.
FAQs
How can I use "the reason thereof" in a sentence?
Use "the reason thereof" to refer back to a previously mentioned event or situation in a formal context. For example, "The project failed, and the reason thereof was inadequate planning."
What's a simpler alternative to "the reason thereof"?
You can use phrases like "the reason for that", "the cause of that", or simply "why that happened". These alternatives are less formal and more common in everyday language.
Is "the reason thereof" considered formal or informal?
"The reason thereof" is generally considered formal. It's best suited for academic, legal, or otherwise formal writing. Avoid using it in casual conversation.
What is the difference between "the reason thereof" and "the reasons thereof"?
"The reason thereof" refers to a single cause or explanation, while "the reasons thereof" indicates multiple causes or explanations. The choice depends on whether there is one primary reason or several contributing factors.
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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
84%
Authority and reliability
4.2/5
Expert rating
Real-world application tested