Making assumptions in French (in a nuanced way)
Salut,

I'm asking this in English but I wouldn't mind answers in French. My reading is much better than my writing currently.

So I want to state that I make an assumption. All the suitable verbs that I have found look analogous to English counterparts. And because of that, I have assumptions as to their proper usage:

assumer - the English verb to assume is used in a neutral fashion. It can mean an assumption in mathematics. I would say it doesn't reveal anything about how I assess the odds of my assumption being true.

supposer - "I suppose" is used similar to "I guess", so it sounds like I am rather uncertain.

présumer - I would "presume" sth if there is very strong reason to think sth is the stated way. Let's imagine I have an 18-year old before me and am typing his or her personal data into a computer, I would maybe ask "Je présume que vous êtes célibatair/-e...?" because of the age.

Please tell me if I am missing other expressions! Merci.

Question

Making assumptions in French (in a nuanced way)
Salut,

I'm asking this in English but I wouldn't mind answers in French. My reading is much better than my writing currently.

So I want to state that I make an assumption. All the suitable verbs that I have found look analogous to English counterparts. And because of that, I have assumptions as to their proper usage:

assumer - the English verb to assume is used in a neutral fashion. It can mean an assumption in mathematics. I would say it doesn't reveal anything about how I assess the odds of my assumption being true.

supposer - "I suppose" is used similar to "I guess", so it sounds like I am rather uncertain.

présumer - I would "presume" sth if there is very strong reason to think sth is the stated way. Let's imagine I have an 18-year old before me and am typing his or her personal data into a computer, I would maybe ask "Je présume que vous êtes célibatair/-e...?" because of the age.

Please tell me if I am missing other expressions! Merci.

Answer

Hi !
« Assumer » in French is more often used to say that you’re taking the responsibility for an action. It can sometimes be used in the same way than the English verb “Assume”, but it's unusual.

When you “suppose” something, you admit that it is probable. “Présumer” is a synonym.

You can also use verbs as “penser” or “croire”. For example: je crois/pense qu’il va bientôt pleuvoir (it may rain but I’m not 100% sure). 
Sometimes, you can also find the verb “imaginer”: J’imagine qu’il n’a toujours pas payé la facture (you make an assumption that sounds like a reproach).

I hope this will help :)