What it means
にせよ expresses a concession: even if something is the case, or granted that it is the case, the main statement still applies. It is commonly used in formal writing, speeches, discussions, and structured arguments. It can follow a plain verb or an i-adjective, and it can follow a noun or na-adjective with である. The form often appears with たとえ, but たとえ is optional. It may also be repeated in patterns such as にせよ…にせよ to mean “whether…or…”.
Usage note
にせよ is formal and is not itself a polite sentence ending. The less formal counterpart にしろ is often used in familiar sentences, while にせよ is preferred in formal or written contexts. Do not confuse this concessive use with the imperative meaning of related forms such as せよ.
How to use it
たとえ専門家であるにせよ、最終判断は委員会が下します。
Even if they are an expert, the committee makes the final decision.
たとえ不完全であるにせよ、現段階ではこの案を採用します。
Even if it is incomplete, we will adopt this proposal at this stage.
たとえ遠いにせよ、現地を自分の目で確認します。
Even if it is far away, I will confirm the site with my own eyes.
たとえ結果が予想を上回るにせよ、追加の検証を行います。
Even if the result exceeds expectations, we will conduct additional verification.
たとえ専門家であるにしろ、最終判断は委員会が下す。
Even if they are an expert, the committee makes the final decision.
たとえ不完全であるにしろ、現段階ではこの案を採用する。
Even if it is incomplete, we will adopt this proposal at this stage.
たとえ遠いにしろ、現地を自分の目で確認する。
Even if it is far away, I will confirm the site with my own eyes.
たとえ結果が予想を上回るにしろ、追加の検証を行う。
Even if the result exceeds expectations, we will conduct additional verification.
Example sentences
たとえ準備が不十分であるにせよ、予定どおり発表を始めなければならない。
Even if the preparations are insufficient, we must begin the presentation as scheduled.
結果が不確実であるにせよ、研究を続ける価値はある。
Even if the result is uncertain, it is worth continuing the research.
たとえ費用が高いにせよ、安全性を優先してこの