Main Difference
The main difference between Preposition and Proposition is that the Preposition is a a word or phrase able to connect a following noun or noun phrase (and often other parts of the speech) as a complement to some other part of the sentence, expressing a relation between them and Proposition is a statement of what is believed.
Proposition
The term proposition has a broad use in contemporary analytic philosophy. It is used to refer to some or all of the following: the primary bearers of truth-value, the objects of belief and other “propositional attitudes” (i.e., what is believed, doubted, etc.), the referents of that-clauses, and the meanings of declarative sentences. Propositions are the sharable objects of attitudes and the primary bearers of truth and falsity. This stipulation rules out certain candidates for propositions, including thought- and utterance-tokens which are not sharable, and concrete events or facts, which cannot be false.
Preposition (noun)
Any of a class of non-adjectival or adverbial sense, with some other word: a particle used with a noun or pronoun (in English always in the objective case) to make a phrase limiting some other word.
Preposition (noun)
A proposition; an exposition; a discourse.
Preposition (verb)
To place in a location before some other event occurs.
“It is important to preposition the material before turning on the machine.”
Proposition (noun)
The act of offering (an idea) for consideration.
Proposition (noun)
An idea or a plan offered.
Proposition (noun)
The terms of a transaction offered.
Proposition (noun)
In some states, a proposed statute or constitutional amendment to be voted on by the electorate.
Proposition (noun)
A complete sentence.
Proposition (noun)
The content of an assertion that may be taken as being true or false and is considered abstractly without reference to the linguistic sentence that constitutes the assertion; a predicate of a subject that is denied or affirmed and connected by a copula.
““’Wiktionary is a good dictionary’ is a proposition” is a proposition.”
Proposition (noun)
An assertion so formulated that it can be considered true or false.
Proposition (noun)
An assertion which is provably true, but not important enough to be called a theorem.
Proposition (noun)
A statement of religious doctrine; an article of faith; creed.
“the propositions of Wyclif and Huss”
Proposition (noun)
The part of a poem in which the author states the subject or matter of it.
Proposition (verb)
To make a suggestion of sexual intercourse to (someone with whom one is not sexually involved).
Proposition (verb)
To make an offer or suggestion to (someone).
Preposition (noun)
a word governing, and usually preceding, a noun or pronoun and expressing a relation to another word or element in the clause, as in ‘the man on the platform’, ‘she arrived after dinner’, ‘what did you do it for?’.