《史记·七十列传·范雎蔡泽列传》
这话说的很实在啊！范雎、蔡泽是人们所说的一代辩士，然而那些游说诸侯直至白发苍苍也没遇到知音的，并不是计策谋略拙劣，而是使游说获得功效的条件不够。
范雎、蔡泽世所谓一切辩士，然游说诸侯至白首无所遇者，非计策之拙，所为说力少也。
What a profound statement! Fan Ju and Cai Ze were considered to be the greatest lobbyists of their time, but the ones who lobbied the feudal lords until their hair turned white and still did not find a kindred spirit were not less astute in strategy and tactics, but lacked the necessary conditions for their lobbying to be effective.