ものではない
- 1One should not do something; it goes against common sense or proper conduct.Ex. 1
- 2By its nature, something is not the kind of thing that is so or can be done in the stated way (e.g. easily).Ex. 2
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Sense (1) is typical of parents, teachers, or elders admonishing someone about manners or morals, presenting the rule as common sense rather than personal opinion. Sense (2) often follows potential verbs such as できる or わかる, frequently with an adverb like 簡単に, to say something is not naturally or readily the case. The pattern appears in both speech and writing, and ものじゃない and もんじゃない are casual.
Do not use sense (1) toward superiors, because it sounds like a lecture or a scolding.
Note that sense (1) states general social norms, not specific rules or regulations.
Note that sense (2) negates only what follows, so 簡単に解決できるものではない means not easily solvable, not unsolvable.
- というものではないN2「というものではない」is a partial negation meaning 'not necessarily / not enough that...', and attaches to various plain forms; 「ものではない」attaches only to verbs. When negating possibility they are sometimes interchangeable, but 「というものではない」only means 'not necessarily' and sounds softer.
- というものでもないN2「というものでもない」partially negates an assumption, meaning 'it's not that... just because...', and can attach to verbs, adjectives, and nouns; 「ものではない」means 'should not' or 'cannot', and attaches only to verbs, so the two are not interchangeable.
- べきではないN3「べきではない」is close to 「ものではない」only in the 'should not' sense, where they are interchangeable, but it expresses the speaker's own view of right and wrong with a heavier, more assertive tone, can criticize specific actions, and has 「べきではなかった」to express regret; it has no 'cannot' meaning.
- てはならないN2「てはならない」is a formal written prohibition that can be used in explicit legal or regulatory bans; it resembles 「ものではない」only in the 'advising by common sense' sense, where 「ものではない」is softer and also has the 'cannot' meaning, which 「てはならない」lacks.
- べからずN1「べからず」is close only to the advisory sense, but it is a classical-style strong prohibition used mainly on signs and in rules, with a stiff tone; 「ものではない」gives gentle advice based on common sense in a neutral register. 「べからず」does not express the negation-of-possibility meaning.
というものではない and というものでもない give a partial negation ('it's not necessarily the case that…', the latter being softer), whereas ものではない admonishes or firmly denies that something is naturally so. べきではない expresses the speaker's own judgment of what is right, てはならない states a prohibition or rule, and べからず is a stiff, archaic prohibition seen on written notices, while ものではない appeals to common sense.
