In 15 Seconds
- Used to link a conclusion to an initial assumption.
- Common in logical arguments, planning, and debates.
- Means 'based on what we agreed to assume earlier'.
Meaning
This phrase is used to say that something is true based on a starting assumption or a 'what if' scenario you previously established.
Key Examples
3 of 6Planning a group dinner
Si tout le monde vient, par l'hypothèse, il nous faut vingt chaises.
If everyone comes, by the hypothesis, we need twenty chairs.
Discussing a work project
Si le budget est validé, par l'hypothèse, nous commençons lundi.
If the budget is approved, by the hypothesis, we start on Monday.
Texting about a potential date
S'il est libre ce soir, par l'hypothèse, on se voit à huit heures ?
If he's free tonight, by the hypothesis, we're meeting at eight?
Cultural Background
The French education system (the 'Bac') places a massive emphasis on philosophy and logic. 'Par l'hypothèse' is a phrase every student learns to use in their final year essays. In Quebec, the legal system (Civil Law) is based on the French model, making this phrase very common in legal judgments and formal administrative documents. In Swiss French, particularly in the banking and diplomatic sectors of Geneva, this phrase is used to maintain a high level of precision in negotiations. Globally, French-speaking academics use this phrase as a 'shibboleth'—a sign of intellectual rigor and belonging to the formal scientific community.
Use it in the DELF/DALF
Using 'par l'hypothèse' in your B2 or C1 writing exam will instantly signal to the examiner that you have a high level of academic French.
Don't over-use it
If you use it more than once or twice in a short text, you will sound repetitive and overly pedantic.
In 15 Seconds
- Used to link a conclusion to an initial assumption.
- Common in logical arguments, planning, and debates.
- Means 'based on what we agreed to assume earlier'.
What It Means
Think of par l'hypothèse as a logical anchor. It is a way of saying, "Remember that thing we just assumed was true? Well, because of that, this next part must also be true." It is not just about science or math. It is about keeping your story or argument consistent. If you start a conversation by saying "Let's assume we are rich," then par l'hypothèse, you can afford that yacht. It links your current conclusion back to your original premise. It is a very structured way to speak. It shows you are following a clear line of thought.
How To Use It
You usually drop this phrase into the middle or end of a sentence. It acts as a justification. You first set a condition using si (if) or supposons que (let's suppose). Then, when you reach a conclusion, you add par l'hypothèse to show the logic. For example, if you are planning a road trip and assume the car works, then par l'hypothèse, you will arrive on time. It is like a verbal receipt for your logic. It keeps everyone on the same page during a complex explanation. You can use it to sound smart or just to be very clear.
When To Use It
Use it whenever you are building a case or a plan. It is perfect for business meetings when discussing projections. "If sales grow by 10%, par l'hypothèse, we can hire more staff." It also works in debates with friends. If you are arguing about a movie plot, use it to point out inconsistencies. It is very common in academic writing or legal contexts. However, you will also hear it in daily life when people are being slightly pedantic or very organized. It is great for "what-if" games or planning logistics for a big event.
When NOT To Use It
Do not use this for simple facts that do not need an assumption. You would not say "The sun is hot par l'hypothèse." That is just a fact. Also, avoid it in very high-energy, emotional rants. It sounds too cold and calculated for a heated argument with a partner. If you are at a loud party, it might sound a bit too formal or "nerdy." It requires the listener to follow a logical chain. If people are just looking for quick small talk, skip the logical connectors. It can feel a bit stiff if overused in casual texting.
Cultural Background
France is the land of René Descartes and rationalism. Logic is deeply embedded in the French education system. From a young age, French students are taught the "thèse-antithèse-synthèse" method of arguing. Using phrases like par l'hypothèse is a reflection of this cultural love for structure. Even in casual conversation, French speakers appreciate a well-constructed argument. It is not just about being right; it is about how you get there. This phrase is a small tool in that grand tradition of French intellectualism. It makes you sound like a thinker.
Common Variations
You might hear selon l'hypothèse (according to the hypothesis). Another common one is dans cette hypothèse (in this hypothesis/scenario). If you want to be less formal, you can say si c'est le cas (if that's the case). Scientists might use par hypothèse without the article l'. In everyday speech, people often just say du coup (so/therefore), but par l'hypothèse adds a layer of "I am being very precise here." It is the difference between a rough sketch and a blueprint.
Usage Notes
This phrase is a marker of logical discourse. It is most effective in debates or planning sessions where you need to maintain a clear line of reasoning.
Use it in the DELF/DALF
Using 'par l'hypothèse' in your B2 or C1 writing exam will instantly signal to the examiner that you have a high level of academic French.
Don't over-use it
If you use it more than once or twice in a short text, you will sound repetitive and overly pedantic.
The 'Cartesian' vibe
When you use this, you are channeling 'L'esprit cartésien'. It implies you are a logical, clear thinker.
Examples
6Si tout le monde vient, par l'hypothèse, il nous faut vingt chaises.
If everyone comes, by the hypothesis, we need twenty chairs.
Linking the number of chairs to the assumption that everyone attends.
Si le budget est validé, par l'hypothèse, nous commençons lundi.
If the budget is approved, by the hypothesis, we start on Monday.
Setting a clear timeline based on a condition.
S'il est libre ce soir, par l'hypothèse, on se voit à huit heures ?
If he's free tonight, by the hypothesis, we're meeting at eight?
Using logic to confirm plans over text.
Si je suis invisible aujourd'hui, par l'hypothèse, ces calories ne comptent pas.
If I am invisible today, by the hypothesis, these calories don't count.
Using formal logic for a silly, relatable excuse.
Si tu ne m'aimes plus, par l'hypothèse, notre voyage n'a plus de sens.
If you no longer love me, by the hypothesis, our trip no longer makes sense.
Applying logic to a painful realization.
En admettant que x soit égal à y, alors par l'hypothèse, le résultat est nul.
Assuming x equals y, then by the hypothesis, the result is zero.
Classic academic use in a mathematical context.
Test Yourself
Complete the sentence with the correct form of the phrase.
Si nous supposons que A = B, alors ___ , B = A.
In a logical statement starting with 'supposons', we use 'par l'hypothèse' to link the conclusion.
Which sentence uses the phrase correctly in a formal context?
Choose the best option:
This sentence uses the phrase to describe a logical consequence of a specific scenario (a strike).
Fill in the missing line in this formal debate.
Speaker A: 'Admettons que le budget soit réduit de moitié.' Speaker B: 'Alors, ___ , nous devrons licencier du personnel.'
Speaker B is drawing a direct logical conclusion from Speaker A's assumption.
Match the phrase to the correct situation.
Where would you most likely hear 'par l'hypothèse'?
The phrase is academic and formal, making it perfect for a university setting.
🎉 Score: /4
Visual Learning Aids
Contexts for 'par l'hypothèse'
Academic
- • Math proofs
- • Philosophy
- • Science
Professional
- • Strategy
- • Legal
- • Finance
Practice Bank
4 exercisesSi nous supposons que A = B, alors ___ , B = A.
In a logical statement starting with 'supposons', we use 'par l'hypothèse' to link the conclusion.
Choose the best option:
This sentence uses the phrase to describe a logical consequence of a specific scenario (a strike).
Speaker A: 'Admettons que le budget soit réduit de moitié.' Speaker B: 'Alors, ___ , nous devrons licencier du personnel.'
Speaker B is drawing a direct logical conclusion from Speaker A's assumption.
Where would you most likely hear 'par l'hypothèse'?
The phrase is academic and formal, making it perfect for a university setting.
🎉 Score: /4
Frequently Asked Questions
10 questionsNo. 'Supposons' (let's suppose) starts the hypothesis. 'Par l'hypothèse' (by the hypothesis) refers back to it to draw a conclusion.
Only if you are being ironic or joking about being very formal. Otherwise, it's too stiff for texting.
It's the definite article. In French, abstract nouns like 'hypothèse' usually require an article, even in fixed phrases.
Yes, it is extremely common in scientific papers to describe the results of a model or experiment.
There isn't a direct opposite, but 'en réalité' (in reality) is often used to contrast a logical assumption with the actual facts.
Yes, you can replace 'l'' with a possessive adjective if you want to emphasize that it is *your* specific idea.
Much more common in writing. In speaking, it is reserved for formal presentations or debates.
No. It is a prepositional phrase, not a conjunction, so it doesn't affect the mood of the following verb.
Yes, lawyers use it to show that if a certain fact is accepted, a certain legal consequence must follow.
In French, 'th' is always pronounced like a simple 't'. Never like the English 'th'.
Related Phrases
en supposant que
similarassuming that
par définition
similarby definition
ipso facto
similarby the fact itself
admettons que
builds onlet's admit that
