Assumption
Assumption noun - Something taken as being true or factual and used as a starting point for a course of action or reasoning.
Usage example: your argument is faulty because it's based on erroneous assumptions
Proposition is a synonym for assumption in conjecture topic. In some cases you can use "Proposition" instead a noun "Assumption".
Proposition
Proposition noun - An idea that is the starting point for making a case or conducting an investigation.
Usage example: started the discussion with the simple proposition that no one ever does anything out of pure altruism
Assumption is a synonym for proposition in conjecture topic. Sometimes you can use "Assumption" instead a noun "Proposition".
Mutual synonyms
Related pairs
- surmise and assumption
- surmise and proposition
- notion and assumption
- notion and proposition
- undertaking and assumption
- undertaking and proposition
- idea and assumption
- idea and proposition
- conjecture and assumption
- conjecture and proposition
- argument and assumption
- argument and proposition
- supposition and assumption
- supposition and proposition
How words are described
Both words in one sentence
- As with other adversarial proceedings (such as civil and criminal trials), the idea is to thoroughly test an idea or proposition before acting upon it, on the assumption that any concept that withstands intense criticism has a better chance of being correct.
Source: Devil's Advocate
Cite this Source
Proposition and Assumption. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/assumption/proposition
Assumption & Proposition. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/assumption/proposition>.
Proposition or Assumption. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/assumption/proposition.
Google Ngram Viewer shows how "assumption" and "proposition" have occurred on timeline