Presume vs. Assume: When to Use Assume vs. Presume

Presume and assume are two words that have the same root and only differ because they have different prefixes. However, these prefixes play a big role and, as if often happens in the English language, change the meaning of the whole word. Thus, just a few different letters can create confusion in writing and in speaking. But what exactly is the difference between presume vs. assume?

Presume vs. Assume

Key Takeaways

  • When you PRESUME something, you suppose it based on some evidence or probability.
  • On the other hand, when you ASSUME something, you believe so without any evidence.

Presume vs. Assume

Presume vs. Assume: Overview

Defining Presume

Presume generally carries the connotation of belief based on reasonable evidence or probability. When we presume, we are making an inference about something that is likely true, although not proven or certain. For instance:

  • We presume that a colleague who is not at their desk is in a meeting if they have a busy calendar.

Defining Assume

In contrast, assume refers to accepting something as true without proof or on uncertain grounds. It’s often about taking something for granted. When we assume, evidence is not a necessity; it is more about a hypothesis that has yet to be tested or verified. For example:

  • We assume a business will succeed based on a gut feeling rather than an extensive market analysis.

When to Use Presume vs. Assume

Though these definitions are the most common and popular ones, both words have other meanings as well. Presume can also mean “to act without permission” or “to accept something as true because there is no evidence that it is false”. For example, in law, a person can be presumed innocent, since there is no definitive evidence that they are guilty.

As for assume, it can mean “to undertake a task or a responsibility” or “to adopt qualities”. For instance, someone can assume the place of a minister after the previous minister retired.

However, it’s the fact that these two words can be synonymous with “to suppose” or “to take granted” that is causing confusion. Indeed, there is only a slight difference but it is noticeable, especially in formal writing.

Look at a simple example to understand this difference. Here are two sentences that look almost the same:

  1. I presume that Mary will come here at about 3 o’clock.
  2. I assume that Mary will come here at about 3 o’clock.

Though both of these sentences suggest that you expect Mary sometime around 3, each sentence gives some extra information. The first one states that you have some evidence to support your words, e.g. Mary has called you and told you the time when she’ll arrive, or Mary always arrives at the same time. The second sentence, in contrast, shows that you believe that this is what’s going to happen, but you have no actual proof.

In short, as synonyms for suppose, both presume and assume can be used. Still, presume has a stronger meaning and, if you use this verb, it will make your words sound more believable and legit.

Presume vs. Assume Examples

Examples of “presume”

  • presume you’ve finished your homework since you’re watching TV now.
  • The jury must not presume guilt; instead, it should carefully consider all the evidence presented.
  • We presume that the meeting will take place at noon unless we hear otherwise.
  • Based on the empty house and the packed bags, the detectives presumed that the family had left in a hurry.
  • Due to his extensive experience in the field, we can safely presume he’s the right candidate for the job.
  • If you don’t RSVP to the invitation, the hosts might presume you’re not coming to the event.

Examples of “assume”

  • He didn’t say anything, but I assume he agrees with the decision since he nodded.
  • Many people assume that a higher price tag means better quality, but this isn’t always the case.
  • When you didn’t show up on time, we had to assume you got caught in traffic.
  • It’s not safe to assume that the ice is thick enough to walk on without checking first.
  • She will assume the role of director in the upcoming play.
  • The new manager will assume his duties starting next Monday.

Frequently Asked Questions

What is the main difference between ‘presume’ and ‘assume’?
We use ‘presume’ when we have some evidence or indication leading to a belief, but it’s not concrete. With ‘assume’, no evidence is needed; we simply take it as true without proof.

Can ‘presume’ and ‘assume’ be used interchangeably?
While they are often used similarly, we don’t recommend using them interchangeably. The nuance in their meaning is crucial, as ‘presume’ suggests a higher likelihood based on some evidence, whereas ‘assume’ is more speculative.

Are there certain contexts where one is preferred over the other?
Yes, in legal or formal contexts, ‘presume’ is often preferred due to its implication of an existing basis, whereas ‘assume’ tends to be used in more informal or general situations.

How do we use these words in a sentence?
When we say, “We presume the meeting will start at 9 AM based on the schedule,” we imply there is a schedule that indicates this. If we say, “We assume everyone will want lunch,” it’s a general belief without specific evidence.