Is it safe to assume that "assume" and "presume" follow the same rules? They sound similar, have overlapping meanings, and often get used interchangeably. But when was the last time you heard someone say "assumptuous?"
Presumably never. After all, the only safe assumption about English is that there aren't any safe assumptions.
While it's true that both "assume" and "presume" can mean “to take for granted,” they tend to have different connotations.
"Presume" tends to suggest a stronger level of confidence—sometimes too strong. When we presume something, it’s usually based on some evidence. There's a hint of boldness, maybe even arrogance.
On the other hand, "assume" often means something closer to "suppose." For example, if we're arguing with someone, we might assume something for the sake of argument, which is more hypothetical than a presumption.
While researching "assume," we were struck by its range of meanings, including "to receive into partnership" or "to receive up into Heaven.” It can mean "to undertake an office or a duty," as in "assume a role" or "assume office." It can also mean "pretend to have" as in "assume an air of modesty,” among other things.
There's definitely some overlap in meaning between "assume" and "presume," but "presume" carries a few distinct meanings.
It can mean “to take upon oneself,” often without permission or authority, as in “to presume too much familiarity.” Historically, it even meant “to seize.” In legal contexts, it’s used to mean “to suppose something is true without proof”—as in “presumed innocent until proven guilty.”
"Presume" also gives us two adjective forms: "presumptuous" and "presumptive." Back in the 1600s, these were basically synonymous. There’s evidence as early as the 1600s that they both meant “too boldly” or “unduly confident” or “impertinent.” Basically, they meant what we now think of as the common meaning of “presumptuous.”
Today, “presumptive” has diverged in large part to describe something that’s assumed based on probability, as in “presumptive heir,” or to refer to things that give us reasonable grounds for inferring or presuming things, such as “presumptive evidence.”
That brings us back to our original question: If we can be "presumptuous" why can't we be "assumptuous?" To hear our discussion on that, listen to the audio above.
