hand-wavy

昨日ブログに日記を投稿直後に電話があり、福岡の親戚に不幸があり、慌てて福岡に日帰りで行ってきました。福岡発の最終便に乗ったのですが３０分ほど出発が遅れたの家に帰る最終便にやっと間に合うヒヤヒヤものでした。
さて、ＲＤ１０月号のErik Demaineの記事からの最後の引用です。
"Maybe in the real world, there is a very thin fourth dimensions, a spatial dimension - physicists believe that this might be the case. And perhaps by simulating things in four dimensions, and then kind of squeezing that fourth dimension out, we can understand how proteins fold in three dimensions," Ask for further details and Demaine admits, "Here things get a little hand-wavy."
"hand-wavy" の意味が分からないので辞書を引きます。 しかし、"hand-wavy" の説明を載せている辞書は見つかりませんでしたが、Wiktionaryに "handwavy" とも綴られるとし、次ぎの説明がありました。
・Wiktionary: Of a demonstration, proof, or explanation, missing important details or logical steps, perhaps instead appealing to common sense, tradition, intuition, or examples.
そして動詞の "handwave" を、
To explain something, but skip over important details, perhaps appealing to intuition instead
と説明しています。 "handwavy"/ "handwave" なら説明を載せている辞書は少し増えますが、Oxford English Dictionary、Merriam-Webster's Online Dictionaryなどの一般的な辞書にはやはり掲載されていません。
しかし、Wikipediaに "handwaving" の説明がありましたので引用します。
The term handwaving is an informal term that describes either the debate technique of failing to rigorously address an argument in an attempt to bypass the argument altogether, or a deliberate gesture and admission that one is intentionally glossing over detail for the sake of time or clarity. It can be meant as an accusation or in a more positive light, depending on the context. It is also used in other situations, as for instance, "The Council has merely handwaved a solution to the traffic dangers at this intersection", meaning a claim of solution without actuality. In this sense, the solution has been achieved by public relations manipulations.
話をする時に西洋人は日本人よりもジェスチャーが多いと聞いていますが、言葉だけでは通じない話は "handwavy" と言うのはやはり言い過ぎでしょうね。