Presume vs assume?

The verbs presume and assume each mean “take for granted,” but assume also describes the act of pretending, absorbing responsibility, or taking over a role. A presumption also involves an educated guess, while an assumption lacks evidence.

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What is the difference between presume and assume?

Whether you’re learning English as an ESL student or brushing up on your writing skills, learning the differences between presume and assume is confusing. Presume and assume share similar contexts, word origins, and pronunciations, but they have different meanings. 

The words presume and assume share the same connotation when they describe unjustified opinions and behavior. In this sense, the main difference between the two verbs is that a presumed belief is more confident than an assumed one. 

When do assume and presume have different meanings?

English speakers also use the word assume to describe the act of pretending, taking something over, hiring, or absorbing a debt. In this sense, the verb assume implies how the act of “taking something on” can be literal, whether it’s an identity, an employee, or a garment. 

Is an assumption a guess?

All guesses are contrived ideas with various degrees of logic, so guesses are either presumptions or assumptions. For instance, if someone asked you for the time of day and the sun was halfway through the sky, you might presume that it’s noon. In this case, a presumption is a guess that’s based on reasonable evidence.

An assumption is a guess that possesses less evidence. Unlike an educated guess, we make assumptions from beliefs instead of facts. 

For example, let’s say you’re a student and you’re about to finish a class. You’ve earned an A- so far, so you assume that if you skip the final exam, you’ll still pass the class with a C. What you don’t know is that the syllabus states “final exam is mandatory.” Inevitably, you fail the course because you believed something that you told yourself.

To illustrate further, let’s compare assume and presume in the following news excerpts:  

“Bad guys can no longer assume they will get away with crimes by simply running away.” –– The Washington Post 
“When abduction is followed by murder, court can presume that abductor is the murderer.” –– Live Law

For the first sentence, the word assume describes how “bad guys” believe they can get away with crimes if they run away. The bad guys believe this is possible, despite the lack of evidence to support their belief. The key trait of an assumption is that it’s upheld by a self-informed guess.

In the second example, the court presumes (or “believes”) that an abductor is a murderer because it’s a likely conclusion. Unlike an assumption, a presumption is upheld by an educated guess. 

Phrases related to assume and presume

Phrases like “take for granted” or “make-believe” also highlight the slight differences between assume and presume. For instance, the phrasetake for granted” encompasses both verbs because it describes a belief or an expectation that is upheld by implied truths instead of reality. 

For example, 

“Before the pandemic, we took toilet paper for granted. Nobody anticipated a mass shortage in 2020.” 
“Younger generations take Google for granted. My generation had to explore the Dewey Decimal System to learn anything.” 

In contrast, the verb assume is synonymous with the phrase “make-believe,” which describes the act of feigning an identity or personality under false pretenses. For example,

“Whenever I feel awkward, I make believe I’m invisible.” 
“When it snows, the children make-believe that they live at the North Pole.”

What does presume mean?

The word presume (also, presumed or presuming) is a verb that describes the act of believing something because it’s “probably” true, instead of a sure fact. Sentence examples include, 

“Resident At Heritage Receives ‘Presumed Positive’ Test For COVID.” –– The Post-Journal 
“Critics say that keeping defendants locked up in court presumes guilt …” 
“‘Why on earth do we want to marginalize somebody who is presumed innocent in this way?”’ –– The New York Times

Most people consider presumptuousness (noun) to be rude because presumptuous (adj.) behavior often occurs without consent or justification. The key trait of someone who acts “presumptuously” (adverb) or “in a presumptuous manner” is that their action goes beyond what’s appropriate or courteous for the situation. 

Synonyms of presume

Assume, believe, conceive, conjecture, daresay, expect, guess, hypothecate, hypothesize, imagine, postulate, premise, presuppose, speculate, suppose, surmise, suspect, suspicion, theorize.

Antonyms of presume

Ascertain, challenge, controvert, demonstrate, determine, discredit, dispute, document, establish, learn, prove, repudiate, substantiate, question, validate.

Etymology of presume

The word presume entered the English Language in Late Middle English from Old French presumer. According to Lexico, Old French presumer stems from Latin praesumere, which means ‘anticipate’ or ‘take for granted.’ 

What does assume mean?

The verb assume (also, assumed or assuming) describes the act of supposing something to be true without evidence, adopting a responsibility without being asked, or acting under an implied truth. 

Assumable (adj.) behavior is assumably (adverb) absent of justification, detached from reality, or associated with power and control. However, the state of assumability (noun) is entirely related to banking and finance, and it involves the act of absorbing the financial responsibilities of an estate’s previous owner. 

Specific definitions and examples of assume include: 

1. To undertake a responsibility, volunteer, or expect something without being asked, or; to seize power or control over something. For example,

“When you are faced with people who assume they are invited, let them know you feel honored that they would want to come.” –– Chicago Tribune
[sports player] to assume more ownership in Rams offense this season.” –– 247 Sports
“Chief judge to assume circuit court judgeship.” –– Apalach Times

2. To suppose something to be true without evidence. 

“The people in Cometa don’t only treasure beauty, they assume it. In a world of distrust and betrayal, they assume there is beauty in each person and in every situation …” –– The New York Times

3. To wear something, such as clothing or jewelry, or; to pretend, feign, or adopt an attitude or identity. 

“… wigs have been a necessary staple in the toolbox of props that aid an actor in assuming a character.” –– The New York Times
“Watch Martin Short, Maya Rudolph assume awful Chicago accents in spoof.” –– Chicago Tribune 

4. To take responsibility for another person’s debt (i.e., assumability, a banking term for ‘inheriting a debt associated with a purchased estate). 

“With inflation now low, some lenders again see a market for assumable fixed-rate loans.” –– The New York Times

Synonyms of assume

Accept, affect, bear, bluff, conjecture, feign, guess, hire, hypothecate, imagine, postulate, premise, presume, recruit, shoulder, simulate, speculate, suppose, take over, undertake. 

Antonyms of assume

Challenge, disavow, disbelieve, discharge, disclaim, discredit, dismiss, disown, establish, prove, refute, repudiate, sack, validate.

Etymology of assume

The word assume is a Late Middle English term that stems from Latin assumere, which consists of ad- for ‘towards’ and the Latin verb sumere for ‘take.’ Words like “consume” also use sumere for the meaning of “take up.”  

How to remember the difference between assume and presume?

If you need help remembering the difference between assume and presume, try using the following mnemonic:

P is for presume = probable

Since a “presumed” idea is one that functions off of an estimate or likelihood, try associating the letter “p” of “presumed” with the word “probable.” 

A is for assume = appropriate

The word assume involves the act of taking over, pretending, or surmising something to be true. Therefore, we can associate the letter “a” with the verb “appropriate.” 

The verb appropriate means “taking something for one’s own” and, oftentimes, without someone’s permission. In this sense, one can take an idea, identity, attitude, culture, or position–– just like the verb “assume.”

FAQs: Related to assume vs. presume

Are the words assume and presume homonyms?

Assume and presume are near-homonyms, but not exact ones. A homonym is a linguistic term that encompasses homographs and homophones:

  • A homophone is a set of words with similar pronunciations but different meanings and spelling. 
  • A homograph is a set of words with the same spelling but different pronunciations and definitions. 

Presume and assume sound similar, but we pronounce presume with a distinct consonant: 

Presume: “pre-z-oom” (/prəˈz(y)o͞om/)

Assume: “eh-soom” (/əˈso͞om/)

Examples of true homonyms include:

Test Yourself!

Do you understand the subtle differences between presume and assume? See how much you’ve learned with the following multiple-choice questions. 

  1. Word choice: select the best synonym for assume. 
    a. Challenge
    b. Demonstrate 
    c. Feign
    d. Question
  2. Word choice: select the best synonym for presume.
    a. Validate
    b. Theorize 
    c. Prove
    d. Establish
  3. Which of the following phrases encompass the meanings of assume and presume? 
    a. Take for granted
    b. Take someone up on something
    c. Make-believe 
    d. A and B
  4. A person who acts presumptuously is considered ______________?
    a. Unassuming 
    b. Modest 
    c. Rude
    d. Courteous 
  5. True or false: An assumption is a guess with reasonable evidence. 
    a. True
    b. False
  6. Bonus question: “The court system _____________ innocence until proven guilty, so the burden of proof falls on the prosecution.” 
    a. Assumes
    b. Presumes
    c. A and B
    d. None of the above

Answers

  1. C
  2. B
  3. A
  4. C
  5. B
  6. B

Sources

  1. Assume.” Cambridge Dictionary, Cambridge University Press, 2020.
  2. Assume.” Lexico, Oxford University Press, 2020.
  3. Assume.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., 2020.
  4. Brodesser-Akner, T. “Assuming the Right Locks for the Part.” The New York Times, 23 Mar 2012. 
  5. Brooks, D. “The Loving Place for Children That Assumes Beauty.” The New York Times, 30 Apr 2018. 
  6. Greenspan, H.H. “Here’s what to do when people assume they’re invited to your wedding.” Chicago Tribune, 6 Mar 2020. 
  7. Herszenhorn, D.M. “Presumed Innocent, but Caged in Court.The New York Times, 18 Nov 2013. 
  8. Make-believe.” The Merriam-Webster.com Thesaurus, Merriam-Webster Inc., 2020.
  9. Presume.” Cambridge Dictionary, Cambridge University Press, 2020.
  10. Presume.” Lexico, Oxford University Press, 2020.
  11. Presume.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., 2020.
  12. Ravo, N. “Assumable Mortgage Is Trying a Comeback.” The New York Times, 8 Jan 1994. 
  13. Rezaian, J. “A judge’s death highlights the moral rot and corruption in Iran’s legal system.” The Washington Post, 27 June 2020. 
  14. Take for granted.” The Merriam-Webster.com Thesaurus, Merriam-Webster Inc., 2020.