Should I use the subjunctive mood or the indicative mood with the verb "supposer"? Examples:
- Je suppose qu'il fait/fasse toujours ça. (= I assume that he always do that)
- Supposons qu'elle est/soit coupable. (= Let's assume that she is guilty)
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Sign up to join this communityShould I use the subjunctive mood or the indicative mood with the verb "supposer"? Examples:
When supposer is followed by a dependent clause beginning with que, the verb in the dependent clause may be in the subjunctive mood or in the indicative mood depending on what supposer expresses.
When it expresses an assumption we use the indicative:
When it expresses an hypothesis we use the subjunctive. This is the case with : En supposant que, supposé que, à supposer que, supposons que:
I
There exists a first sense for which the indicative is correct (A 1. b). The verb means "to accept as true, as probable".
b) [Le compl. d'obj. est une complét. introd. par que] Considérer quelque chose comme probable; poser quelque chose comme hypothèse.
[Le verbe de la sub. est à l'ind. indiquant la certitude de l'assertion] Admettre comme certain (ce qui va suivre).
(user LPH's bold type)
More examples from the literature
As the meaning of "assume" is taken to be "to take for granted" one should always say "Je suppose qu'il fait toujours ça.". However, "Je suppose qu'il fasse toujours ça." is a correct grammatical possibility; you just can't take "to assume" to mean "to take for granted" any more and you must use the meaning "suppose for the sake of argument" that "to assume" also has.
II
There is a second sense (A 1. b), connected to the preceding, for which the subjunctive must be used. The meaning is that of strict supposition, that of stating a hypothesis.
b) [Le compl. d'obj. est une complét. introd. par que] Considérer quelque chose comme probable; poser quelque chose comme hypothèse.
[Le verbe de la sub. est au subj., empl. pour un tour hyp.] Émettre une hypothèse
(user LPH's bold type)
More examples from the literature (also mathematics, science)
Exceptions¹
In this context of pure hypothesis one finds often the form "supposons" or "supposez" and "supposes" (imperative) but "supposer" in the indicative is also possible. So, one should never say "Supposons qu'elle est coupable." if this is "supposer" in the sense of "assuming for the sake of argument". However, as can been seen from the examples, the exceptions made by the writers, faulty uses should we say, are not so rare.
¹The number of examples as compared to that in the preceding set of examples is not representative of the proportion of exceptions, which is quite low.