nothing but; none other than~
Emphasizes that something is exactly or precisely X, often used to state a cause or identity with conviction.
This pattern means 'nothing but' or 'none other than'. It is a strong, emphatic way to say that something is exactly the thing you mention, often used when giving a reason, cause, or identity. For example, if you say '彼の成功は努力にほかならない', you mean his success is due to nothing but effort. It carries a formal, written, or rhetorical tone, so it is common in speeches, essays, and news, but less common in casual conversation. In speech, you might hear it in formal announcements or when someone wants to make a firm statement.