“(Referring to the Kuomintang) There are many stubborn elements, graduates in the speciality schools of stubbornness. They are stubborn today, they will be stubborn tomorrow, and they will be stubborn the day after tomorrow. What is stubbornness (wan gu)? "Gu" is to be stiff. "Wan" is to not progress: not today, nor tomorrow, nor the day after tomorrow. People like that are called the "stubborn elements". It is not an easy thing to make the stubborn elements listen to our words.”
Mao, 1967, as quoted by Jing Huang in The Role of Government Propaganda in the Educational System during the Cultural Revolution in China http://www.pem.cam.ac.uk/wp-content/uploads/2013/04/Cultural-Revolution-in-China-paper.pdf.
Original
(論國民黨) 有很多的頑固分子,他們是頑固專門學校畢業的。他們今天頑固,明天頑固,後天還是頑固。什麼叫頑固?固者硬也,頑者,今天、明天、後天都不進步之謂也。這樣的人,就叫做頑固分子。要使這樣的頑固分子聽我們的話,不是一件容易的事情。
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Mao Zedong 181
Chairman of the Central Committee of the Communist Party of… 1893–1976Related quotes

Wayne, in a 1 May 1794 letter to the contractors who had failed to properly provision the Legion of the United States.
Attributed
Source: [Sword, Wiley, President Washington's Indian War: The Struggle for the Old Northwest, 1790-1795, Norman, University of Oklahoma Press, 1985, 0-8061-2488-1, 265]

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Source: The Lover's Dictionary