得る（える）

1. Meaning and Usage
得る（える） indicates that an event or state is not impossible within the realm of logic, nature, or human experience. It is frequently used in academic, journalistic, or formal contexts. Note that this grammar point functions as a suffix attached to verbs, which is distinct from the standalone verb 得る（える） meaning 'to gain' or 'to obtain' (e.g., 知識を得る - to gain knowledge). When used as a grammar suffix, it is very commonly written in kanji (e.g., あり得る, 起こり得る), though hiragana (〜うる / 〜える) is also used. Furthermore, in practice, 〜得る attaches to both non-volitional verbs (indicating that an event 'can happen', e.g., ある, なる, 起こる) and volitional verbs (indicating that it is theoretically possible for someone to do something, e.g., 誰もが間違いを犯し得る - Anyone can make a mistake / 想像し得る最悪の事態 - The worst situation one could possibly imagine). However, it is worth noting that while it is frequently seen with native verbs like ある, 起こる, and 考える, it is also highly productive and commonly attaches to Sino-Japanese suru-verbs (e.g., 予想し得る, 理解し得る).

Important Warning: 〜得る cannot be used to express personal ability, physical capability, or acquired skills. For example, you cannot say ❌「私は日本語を話し得る」 to mean 'I can speak Japanese.' For personal abilities, you must use standard potential forms like the potential form or ことができる.

2. Conjugation and Pronunciation
This pattern attaches to the masu-stem of a verb. It has a unique 'split' pronunciation based on its classical roots:

• Dictionary Form: Can be read as 得る（える） (modern) or 得る（うる） (formal/literary). The reading うる is particularly common when the verb precedes a noun (attributive form), such as in あり得る話（ありうるはなし）. Additionally, certain fixed compounds like 考え得る（かんがえうる） and 出来得る（できうる） strongly resist the える reading and are almost exclusively read as うる in their dictionary forms.
• Negative Form: Is always 得ない（えない）. There is no うない.
• Past Form: Is always 得た（えた）. There is no うた.
• Te-form: Is always 得て（えて）.
• Conditional Form: In modern Japanese, defaults to 得れば（えれば）, though classical forms like うれば may appear in highly literary contexts.
• Polite Form: Is always 得ます（えます）.

Rule of Thumb: In modern Japanese, the 'う' reading is primarily used in the dictionary/attributive form (うる). Every other conjugation uses the 'え' reading.

3. Common Phrases and Nuances
While formal, some phrases are very common in daily life:

• あり得る（ありえる・ありうる）: 'It's possible' / 'That could happen.' Note that ありうる is generally preferred over ありえる in formal speech and writing.
• あり得ない（ありえない）: 'Impossible!' / 'No way!' (often used to express shock). Note that this is heavily used in casual, everyday spoken Japanese (even morphing into slang like ありえねー), which is a major exception to the formal nature of this grammar point.
• やむを得ない（やむをえない）: 'Unavoidable' / 'Cannot be helped' / 'Out of one's control'. This is a highly common fixed expression utilizing the 〜得ない pattern.
• 〜得ない with other verbs: When attached to verbs other than ある, the negative form 〜得ない carries a strong nuance of 'there is no possibility of...' or 'cannot happen/cannot do' (e.g., 起こり得ない - cannot happen, 考え得ない - inconceivable, 誰も知り得ない事実 - a fact no one could possibly know).