Green’s Dictionary of Slang

(orig. US) a hard life, seen as a means of education.

1870		Men Who Advertise 161: Trained [...] in the school of hard knocks, he now had learned the theory of success, and from that time on has had it.
1878		Vancouver Indep. 14 Feb. 2/4: There is nothing that so develops a sturdy, self-reliant [...] manhood as to graduate from ‘the college of hard knocks’.
1882		Sedalia Wkly Bazoo (MO) 26 Dec. 7/3: We have all graduated from the College of Hard Knocks, where misfortune [...] and disasters were the professors; kicking, cuffs and blows the curriculum.
1884		R. Rockwell Golden Inheritance 61: ‘After you have been disciplined for a time in the school of hard knocks you will round out most gracefully.’ ‘Is the school of hard knocks a necessary course?’ ‘To most natures it is’.
1892		Dakota Farmers’ Leader (Canton, SD) 5 Feb. 3/5: The School of Hard Knocks was where Andrew Carnegie gained his start.
1904		Aberdeen Jrnl 19 Dec. 4/6: The school of hard knocks in which he was educated made a man of him.
1907		Lexington Advertiser (MS) 26 July 1/5: He [...] knows what it is to ‘handle the smutty end of the chunk.’ The only college he ever graduated from is the College of hard Knocks.
1912		Ade Knocking the Neighbors 24: They had been brought up in the School of Hard Knocks, but they wanted Bertrand and Isabel to go through Life on Ball Bearings.
1912		E. Pugh City Of The World 82: To-day he is taking his first lesson from Hunger in the School of Hard Fact.
1916		P. Kyne Cappy Ricks 248: No young man ever learned a great deal [...] in the college of hard knocks.
1923		Nottingham Eve. Post 2 Feb. 1/2: Few man have had such a fight with poverty in the ‘school of hard knocks’ as the Rev. G.A. Metcalfe.
1925		S. Lewis Arrowsmith 96: The graduates of the University of Hard Knocks judge a physician as they judge a business man.
1931		K.C. Star 23 Oct. n.p.: Looks as if Carnera and Tunney are fraternity brothers in the school of hard knocks [DA].
1936		A. Russell Gone Nomad 13: It was the only university I know—that Bush College of Hard Knocks.
1941		Aberdeen Jrnl 13 Feb. 2/4: Asked by a lady [...] what college he had attended, he replied, ‘The school of hard knocks’.
1951		D. Stivens Jimmy Brockett 52: No school is worth a cracker to you when it came to the real business of life. Myself, I’m a graduate from the school of hard knocks.
1956		‘Ed Lacy’ Men from the Boys (1967) 25: You never needed no bill to go to my college, the University of Hard Knocks.
1960		A. Seymour One Day of the Year (1977) I i: The University of hard knocks, that’s all I ever had.
1968		G. Slatter Pagan Game (1969) 172: Only a bush carpenter, but I’ve travelled, I’ve read, I’ve taught meself in the school of hard knocks.
1978		A. Cornwell ‘Notes from a Gay Black Feminist’ in Jay & Young (1979) 473: There is very little insulation between them and ‘the school of hard knocks,’ as my mother is so fond of calling life in the raw.
1981		J. Wambaugh Glitter Dome (1982) 128: Wilfred James Boyle had been a student in eleven schools of very hard knocks.
1996		K. Lette Mad Cows 117: The school of hard knocks has an accelerated curriculum.
1999		‘Master Pimp’ Pimp’s Rap 23: I graduated from pimp school many years ago — at the university of hard Knocks where I received a PhD degree.
2000		Guardian Guide 5–11 Feb. 10: Christian Gangsta rappers can easily match their ‘OG’ counterparts in the school of hard knocks.