Harvard Law School has a legendary address given to incoming students: “Look to your left, look to your right, because one of you won’t be here by the end of the year.” Other law schools has also used this address to incoming students, and other institutions of learning have used the address as well.
 
Several people are credited with the address and it is not known who said it first. Thurgood Marshall said in 1978 (see below) that Charles Hamilton Houston (1895-1950) gave the address to Howard Law School in 1931; Hamilton had graduated from Harvard Law School. Edward H. “Bull” Warren (1873-1945) was given credit in the October 1945 Harvard Law Review. Roscoe Pound (1870-1964), a Harvard Law School dean, is often given the credit. Samuel Williston (1861-1963), a Harvard Law School professor from 1895-1938, has also been given credit (see the 1960 citation below).
 
   
Wikipedia: Harvard Law School
Harvard Law School (also known as Harvard Law or HLS) is one of the professional graduate schools of Harvard University. Located in Cambridge, Massachusetts, it is the oldest continually-operating law school in the United States and is home to the largest academic law library in the world. HLS typically ranks among the top law schools. The U.S. News and World Report law school rankings place it as second, behind Yale Law School.
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This gave rise to the infamous legend of a dean at the school telling incoming students, “Look to your left, look to your right, because one of you won’t be here by the end of the year.” Novels such as Scott Turow’s One L and John Jay Osborn’s The Paper Chase describe such an environment.
   
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The Yale Book of Quotations
Edited by Fred R. Shapiro
New Haven, CT: Yale University Press
2006
Pg. 798:
Edward H. “Bull” Warren
U.S. legal scholar, 1873-1945
[“Address of Welcome” to incoming students at Harvard Law School:]
“Look well to the right of you, look well to the left of you, for one of you three won’t be here next year.”
Quoted in Harvard Law Review, Oct. 1945
 
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The Crozer Quarterly
v. 15 - 1938
Pg. 163:
Are you familiar with the remark which the famous Dean Pound of the Harvard Law School is said to have addressed to his classes at their first meeting?
 
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Texas Law Review
By Texas Bar Association, University of Texas. School of Law, State Bar of Texas, Texas Law Review Association
v. 21 - 1943
Pg. 344:
Spartan Education. By Edward H. Warren. Boston: Houghton Mifflin Co., 1942, Pp. xi, 164. $2.00.
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His success as a law teacher is largely attributable to his brilliant mind, but in part it is also due to the rules that he adopted in the conduct of his lectures, some of which he recounts in this interesting volume. It has often been told how he was accustomed to say in his initial lecture to the first-year class in Property I: “I want each of you to look at your fellow student on your right, now at the one on your left, and remember that only two of you will be permitted to return to the Harvard Law School next year.”
   
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American federation of labor Post-war forum : Hotel Commodore, New York city - April 12th and 13th, 1944 : complete report of proceedings
By American Federation of Labor.
Washington, DC: The Federation
1944
Pg. 24:
He would tell them, “I want each one of you to look at the man on his right. Now take a good look at the man on your left because by the end of this year one of you three won’t be here.” (Laughter.) If I could talk to you as John Q. Public I could tell you “Look at the man on your right; look at yourself, one of you two men is engaged in making money.”
   
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Increasing subsistence allowances for education or training under the servicemen’s readjustment act. Hearings before the Subcommittee on Education, Training, and Rehabilitation… on H.R. 161, 870, 1617, and 2176… March 7, 1947.
By United States. Congress. House. Veterans’ Affairs Committee.
Washington, DC: Government Printing Office
1947
Pg. 84:
There is an old saying in Harvard Law School, “Look at the fellow on the right, and look at the fellow on the left, because one of you is not going to be here next semester.”
     
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Education
v. 71 - 1951
Pg. 271:
DEAN Roscoe Pound of the Harvard Law School is said to have addressed the first year class: “Take a good look at the man on your right, and the man on your left; next year one of you won’t be here.”
     
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Business and Professional Speech
By Lionel George Crocker
New York, NY: Ronald Press Co.
1951
Pg. 109:
The professor who began his lectures with, “Gentlemen, look on your left and on your right. Two of the three of you won’t be here next year when we open” is an example.
     
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Brainpower Quest; a report on a convocation called by the Cooper Union for the Advancement of Science and Art to find new sources from which to draw tomorrow’s leaders in science and engineering
By Andrew A Freeman
New York, NY: Macmillan
1957
Pg. 217:
MODERATOR JANSEN: That reminds me of an incident that happened to my son when he attended Columbia Law School.  In his first year one of his professors said to the students: “Look at your neighbor at your left; look at your neighbor at your right. One of them won’t be here next year.”
   
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Economics:
An introductory analysis
4th edition
By Paul Anthony Samuelson
New York, NY: McGraw-Hill
1958
Pg. 3:
A well-known college dean used to address the entering class: “Take a good look at the man on your right and the man on your left, because next year one of you won’t be here.”
     
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New Jersey State Bar Journal
By New Jersey State Bar Association    
v. 1 - 1960
Pg. 242: 
Perhaps the most concise appraisal of the temperament of the school was the standard welcoming address delivered by Professor Williston to all entering students. “Look at the person to the left of you and the person to the right of you,” he would say. “Next year, one of you will not be back.” And it was true.

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27 June 1964, St. Petersburg (FL) Times, “Cram courses..who needs ‘em?” by Bette Orsini, Magazine, pg. 14, col. 1:
THE big black type in the newspaper ad said: “Planning To Attend College? How Long Will You Remain?”
 
The ad’s first paragraph carried these words:
 
“At a state university, the incoming freshman class is often greeted with a speech that begins, “Look to your right, look to your left. Two out of three of you won’t be here next year.’” The notice reported that a private industrial and clinical psychological services firm would offer intensive four-week summer study courses for high school juniors and seniors and college freshmen and sophomores.
       
13 September 1964, Chicago (IL) Tribune, “Mother Goes Away to College!” by Harriette Behringer, sec. 5, pg. F4:
They told of a recent freshman convocation at which the speaker said: “Look to your right. Look to your left. Only one of you will be here next year.”
 
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Growing Up in America
By Robert A. Rosenbaum
Garden City, NY: Doubleday
1969
Pg. 149:
Look to your left, look to your right: those faces won’t be there four years from now, when you are graduated from this university.
 
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Social Class and College Graduation:
A replication and extension
By Richard T. Campbell
Thesis/dissertation
University of Wisconsin at Madison
1973
Pg. 85”
...several recent national studies as well as Sowell’s research on a Wisconsin cohort have shown that the old cliche thrown at freshmen during initiation ceremonies (“Look to your right, look to your left, next year only one of you will be here”) is true only in a very shortsighted sense.
     
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How To Get Into Law School
By Rennard Strickland
New York, NY: Hawthorn Books
1974
Pg. 138:
The professor says, “Look to your left, look to your right, one of these men won’t be with us when the dust clears.” There was a time when this was true about law schools.
   
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Women and the Power to Change
By Florence Howe, Carnegie Commission on Higher Education
New York, NY: McGraw-Hill
1975
Pg. 51:
Look to your left and look to your right. Two out of three of you will drop out before you are through, probably in the first two years.
 
Thurgood Marshall’s Equality Speech
The following is a speech Marshall gave at the instillation of Wiley Branton to be dean of Howard Law School.
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Speech of
THE HONORABLE THURGOOD MARSHALL
Associate Justice, The United States
Supreme Court
Saturday, November 18, 1978
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Now, think of those good old days. We started at Howard with Charlie Houston as dean…. (Charles H. Houston, Dean of Howard University Law School, 1930-1935).
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In our first year he told us, “Look at the man on your right, look at the man on your left, and at this time next year, two of you won’t be here.” (Laughter)....
 
I know my class started, as I remember, it was around thirty; and it ended up with six.
 
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Broken Contract:
A memoir of Harvard Law School
By Richard D. Kahlenberg
Amherst. MA: University of Massachusetts Press
1999
Pg. 5:
The old story about the Harvard Law School dean telling students (Pg. 6—ed.) on the first day of class, “Look to your left, look to your right, because one of you won’t be here by the end of the year,” has been replaced in recent years by Professor Alan Dershowitz’s adage: “Look to your left and look to your right, because by the time you graduate, there’ll be no Left left.” The tale of fierce academic competition has become a much more telling and damning tale of greed. To try to understand why students change, and how they are able to reconcile liberal politics and the pursuit of careers in corporate law is the central purpose of this book.
 
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Campus Daze: Easing the Transition from High School to College
By George Gibbs
Alexandria, VA: Octameron Associates
2000
Pg. 24:
CHAPTER 4 ACADEMIC LIFE
Look to Your Left, Look to Your Right
Many years ago, the story goes, college deans would “welcome” their incoming classes in some sort of assembly hall by saying, “look to your left, look to your right.”