SOURCE: An introduction to Selected Writings From A Connectionist's Psychology, Appleton-Century-Crofts, Inc., 1949, pp. 1-11.

[In the following introduction to Selected Writings from a Connectionist's Psychology, Thorndike provides an autobiographical account of his life and work.]

I have no memory of having heard or seen the word psychology until in my junior year at Wesleyan University (1893-1894), when I took a required course in it. The textbook, Sully's Psychology, aroused no notable interest, nor did the excellent lectures of Professor A. C. Armstrong, though I appreciated and enjoyed the dignity and clarity of his presentation and admired his skill in discrimination and argument. These discriminations and arguments stimulated me very little, however, and this was later true also of the writings of Ward and Stout. There is evidently some lack in my equipment which makes me intolerant of critical studies unless fortified by new facts or decorated by a captivating style.

The candidates in a prize examination were required to read also certain chapters from James's Principles. These were stimulating, more so than any book that I had read before, and possibly more so than any read since. The evidence is three-fold. I bought the two volumes (the only book outside the field of literature that I voluntarily bought during the four years of college) and read all save parts of the most technical chapters. Though not, I hope, more impertinent than the average collegian, I reproached Professor Armstrong for not having given us James in place of Sully as our text. When, a year later, circumstances permitted me to study at Harvard, I eagerly registered for the course available under James.

During the first semester at Harvard (1895-1896) my program was half English, one-fourth psychology, and one-fourth philosophy, the last at the suggestion or requirement of Professor Royce. The subtlety and dexterity of Royce's mind aroused admiration tinged with irritation and amusement. Most of the students saw him as a prophet, but to me then he seemed too much a performer. Under no circumstances, probably, could I have been able or willing to make philosophy my business. Its stars shone brightly at Harvard in those years (1895-1897); Royce and Santayana were at or near their full glory, and Palmer was, as ever, the perfect expositor, but what I heard from them or about them did not attract me. Later I read the Life of Reason with extraordinary interest and profit, and learned to value the integrity and sincerity and impartiality of Dewey's writings on philosophy as well as on psychology and education; but in general my acquaintance with philosophy has been superficial and casual. Work in English was dropped in favor of psychology in the course of the first graduate year, and, by the fall of 1897, I thought of myself as a student of psychology and a candidate for the Ph.D. degree.

Münsterberg was in Germany from the fall of 1895 to the fall of 1897. During the second half of the period from 1895 to 1896, Mr. Hackett and I had made experiments in a course under the direction of Professor Delabarre, who had charge of the laboratory. During 1896-1897 I first attempted to measure the responsiveness of young children (3-6) to facial expressions or movements made unconsciously as in mind-reading experiments. I would think of one of a set of numbers, letters, or objects (I cannot now recall which or how many.) The child, facing me across a small table, would look at me and guess. If he guessed correctly, he received a small bit of candy. The children enjoyed the experiments, but the authorities in control of the institution would not permit me to continue them. I then suggested experiments with the instinctive and intelligent behavior of chickens as a topic, and this was accepted. I kept these animals and conducted the experiments in my room until the landlady's protests became imperative. James tried to get the few square feet required for me in the laboratory, and then in the Agassiz Museum. He was refused, and with his habitual kindness and devotion to underdogs and eccentric aspects of science, he harbored my chickens in the cellar of his own home for the rest of the year. The nuisance to Mrs. James was, I hope, somewhat mitigated by the entertainment to the two youngest children.

During the two years of study at Harvard, I had supported myself by acting as tutor to a boy. We roomed together, and the incessant companionship and responsibility was burdensome, though he was cheerful, coöperative, and fonder of me than I deserved, and though I learned much practical psychology and pedagogy from the experience. A year free from such labor seemed desirable, so I applied for a fellowship at Columbia. I received the appointment, and upon inquiry was informed by Professor Cattell that an extension of my work on the mental life of animals would be suitable for a doctor's thesis. I continued these experiments with chickens at my parents' home during the summer. I tried white rats also, but I was stupid in handling them and the family objected to the smell, so I let them go.

I came to New York, bringing in a basket my two most educated chickens, from whom I expected in due time a family which would enable me to test the influence of acquired mental traits upon inherited capacity, a foolish project in view of the slow breeding-rate of fowls. I also expected to test the permanence of their learning over a long interval, but never did, the first of a regrettable list of enterprises left incomplete.

Cattell was not only kind, but highly efficient, providing a room in the attic which was ample for my purpose, and giving, as always, sound advice. The freedom from work and worry for money was a great boon. The present policy of universities is to reduce grants for scholarships and fellowships relatively to the number of students, replacing them by loan funds, and this may be wise. But, so far as I can judge, scholarships at Harvard and a fellowship at Columbia increased my productive work in science by at least two years and probably improved its quality.

The motive for my first investigations of animal intelligence was chiefly to satisfy requirements for courses and degrees. Any other topic would probably have served me as well. I certainly had no special interest in animals and had never taken a course in biology until my last year of graduate work, when I worked hard at it and completed a minor for the doctor's degree. The work with monkeys, from 1899 to 1901, was done from the mixture of duty, interest, and desire for good repute which motivates most scientific work. The extension of the fruitful experimental method to representative primates was obviously important. I would have gladly continued the work with the higher apes, but could not afford to buy or maintain them.

In the spring of 1898, I was offered two positions, one as a teacher of psychology in a normal school, the other at a much lower salary as a teacher of education in the College for Women of Western Reserve University. I chose the latter, partly because my brother expected to go there and partly because of the repute of Western Reserve. I spent the summer in reading the facts and important theories about education and teaching. This could then be done if the history of educational practices was omitted. After a year at Cleveland, I was given a trial at teaching psychology and child study at Teachers College, and there I have spent the past thirty-one years.

I have recorded my beginning as a psychologist in detail because it illustrates what is perhaps the most general fact about my entire career as a psychologist later; namely, its responsiveness to outer pressure or opportunity rather than to inner needs. Within certain limits set by capacity and interest I did in those early years and have done since what the occasion seemed to demand. Thus for various courses taught at Teachers College I wrote the Elements of Psychology, Notes on Child Study, Educational Psychology (in three editions, from 1903 to 1914), An Introduction to the Theory of Mental and Social Measurements, and The Psychology of Arithmetic. It has always seemed to me better for an instructor to present his contributions in black and white than to require the labor and risk the errors of note-taking. Thus I have made somewhat laborious researches on mental inheritance, individual and sex differences, memory, work, fatigue, interest, the interrelations of abilities, the organization of intellect, and other topics in educational psychology, because in each case the matter seemed important for theory or practice or both. I planned and directed the psychological work of the New York State Commission on Ventilation, prepared tests for the selection of clerical employees, and served on the Committee on Classification of Personnel in the Army and in various other enterprises because I was told by persons in whom I had confidence that it was in the line of duty. I have written textbooks for children to show that psychology does apply in detail to the work of the classroom. Thus, in 1919, at the request of the faculty of Columbia College, I undertook the responsibility of preparing annually an intelligence examination suitable for use in the selection and placement of freshmen; and in 1922, at the request of Justice Stone, then Dean of the Columbia Law School, I conducted a three-year investigation which resulted in the Capacity Test adopted in 1928 as a part of the system of selection of entrants to the Columbia Law School.

Obviously I have not “carved out my career,” as the biographers say. Rather, it has been a conglomerate, amassed under the pressure of varied opportunities and demands. Probably it would have been wiser to plan a more consistent and unified life-work in accord with interest and capacity, but I am not sure. Even in the case of great men, there is considerable evidence that the man's own interests and plans may not cause a better output than his responses to demands from outside. Under pressure, James wrote the Principles with wailing and gnashing of teeth to fulfill a contract with a publishing firm. Pragmatism and The Will to Believe were done when he was free to choose. An ordinary man of science has probably less reason to put his own plans above those which the world makes for him. So I do not complain of the restrictions imposed by the necessity of earning a living by various drudgeries to which I have been assigned. And I reproach myself only moderately for not having looked and thought longer before leaping to this, that, and the other job.

In the last dozen years I have been enabled by grants from the Carnegie Corporation to carry on two investigations which I did choose and plan, one on the fundamentals of measurement of intellect and capacity, the results of which appeared as The Measurement of Intelligence, the other on the fundamentals of learning, the results of which have appeared in The Fundamentals of Learning and in The Psychology of Wants, Interests, and Attitudes. These do seem to me by far the best work that I have done and I cannot help wondering what would have happened if similar support had been available in 1905 or 1915.

The impetuosity to which I have referred has influenced my work in detail. I often have to do corrective and supplementary experiments and discard work because in its course a better way is found.

Another weakness has been an extreme ineptitude and distaste for using machinery and physical instruments. Presumably my work would have been better, and certainly it would have seemed better, if I had been at home with apparatus for exposing, timing, registering, and the like.

The training which I have most keenly missed has been a systematic course in the use of standard physiological and psychological apparatus and extended training in mathematics. Perhaps the first would not have profited me much in view of my extreme incapacity. I did not lack capacity for mathematics and tried to remedy the second deficiency by private study, but something else always seemed more important. I managed to learn the essentials of statistical method somehow, and have handled some fairly intricate quantitative problems without, I think, making more than one mistake (which I was able to correct promptly at the suggestion of Dr. T. L. Kelley). I feel incompetent and insecure, however, in the abstract algebraic treatment of a quantitative problem and I am helpless when the calculus is necessary.

Young psychologists who share one or more of my disabilities may take comfort in the fact that, after all, I have done useful experiments without mechanical ability or training and have investigated quantitative relations with very meager knowledge of mathematics.

As personal features on the other side of the ledger I may put intelligence, good health, strong eyes, the interest in work and achievement which Veblen has called the “instinct of workmanship,” impartiality, and industry. As environmental features I may note home life with parents of superior intelligence and idealism, many profitable courses at Wesleyan, Harvard, and Columbia, especially those in abnormal psychology with James, statistical methods with Boas, and neurology with Strong, university colleagues eminent in psychology and other fields, and the great body of published work in science.

The last is, of course, the most important. Though an investigator rather than a scholar, I have probably spent well over 20,000 hours in reading and studying scientific books and journals.

I have tried to make two lists, one of authors all or nearly all of whose writings I have read, and another of authors not included in the above to whom I owe valuable facts or suggestions. But the first list of thirty or so names grades off into the names of many more, much of whose writing I have read, and the second list, which is very long, cannot be accurate because of faults of memory. Therefore, I may note only that the writings of James and Galton have influenced me most, and that factual material seems to benefit me more than what is commonly called discussion and criticism. Although, as has been stated, my tendency is to say “Yes” to persons, my tendency seems to have been to say “No” to ideas. I have been stimulated to study problems to which Romanes, Wesley Mills, Stanley Hall, Alexander Bain, Kraepelin, Spearman, and others seemed to me to give wrong answers, more often than to verify and extend work which seemed sound. Of late years this negative or critical tendency seems to have weakened and given place to an interest in questions to which the answers are conflicting or inadequate, and in questions which have not even been faced.

Until the first World War I was able to keep fairly well informed of the findings of psychologists in respect to animal psychology, individual psychology, and educational psychology, but since 1917 I have been able only to follow specially important work and that which I had to know about in connection with my own researches. In spite of the saving of time due to the Psychological Abstracts, my reading is now less and less adequate each year.

I have a suspicion that our scientific code, which demands that an investigator should acquaint himself with everything, good, bad, and indifferent, that has been done on the problem which he is investigating, should be somewhat relaxed. Personally, I seem to have profited more from reading important books outside of the topics I had to investigate, and even outside of psychology, than from some of the monographs and articles on animal learning, intelligence tests, and the like, which our code required me to read.

We are especially urged in these psychological autobiographies to describe our methods of work, but I seem to have little or nothing useful to say in this regard. In the actual work of advancing knowledge of human nature we may use three methods. We may observe and think about the facts that come our way; we may deliberately gather by observation or experiment facts which we see can be got and which seem likely to be instructive; we may pose a question that we know is important and then do our best to get facts to answer it. I have done all three; most often the last. The most fruitful methods often come to mind late in the course of an investigation. When one does everything that he can think of, the doing often makes him think of something else. So the idea of the delayed-reaction experiment (which has proved the most valuable of my methods of studying animal mentality) came to me after two years of work with animals. So the idea that the difficulty of a task for intellect (or any other ability) can be measured only in the case of a task composed of enough elements to involve all of intellect (or of the ability, whatever it may be), and nothing but it, came only after thirty years of study of intellect, and over a year of special investigation of means of measuring difficulty for intellect.

Concerning conditions favorable and unfavorable to scholarly and productive work in science, I have little or nothing instructive to report. Peaceful successful work without worry has rarely tired me, though if I drop below a certain minimum amount of sleep, a headache results. Noise does not disturb me unless it is evidence of distress, as of a person or animal in pain. Surety of freedom from interruption is of course beneficial. Social intercourse except with intimate friends is fatiguing, and all forms of personal conflict, as in bargaining, persuading, or rebuking, are trebly so. Physical exercise is enjoyable, but not, so far I know, beneficial. A general background of freedom from regret and worry is almost imperative, and I early decided to spend so little and earn so much as to keep free from financial worries. In order to reduce one cause for worry, it has been my custom to fulfill my contractual obligations as a professor before doing anything else. The good opinion of others, especially those whom I esteem, has been a very great stimulus, though I have come in later years to require also the approval of my own judgment.

Since my own history is so barren of interest and instruction I may add a few notes of general observation. Excellent work in psychology can surely be done by men widely different in nature or training or both. James and Hall were essentially literary men, one with an extraordinary sense of fact, the other with extraordinary imagination and prophetic zeal. On the other hand, some of our present leaders were first trained in physics or engineering.

Excellent work can surely be done by men with widely different notions of what psychology is and should be, the best work of all perhaps being done by men such as Galton, who gave little or no thought to what it is or should be.

Excellent results have come from the successive widenings of the field of observation to include the insane, infants, and animals, and from the correlation of mental events with physiological changes. Should we not extend our observations to include, for example, history, anthropology, economics, linguistics, and the fine arts, and connect them with biochemistry and biophysics?

The above covers my work till 1934 or age 60. I now (1948) add notes about some activities since then which may be of interest to students of psychology.

It seemed to me that psychology should strive to become a basic science on which Anthropology, Sociology, Economics, Political Science, Law, Criminology, and Philanthropy could count for certain fundamental facts and principles, especially concerning human abilities and wants. With generous aid from the Carnegie Corporation, I spent much time from 1934 to 1940 working with a group of students of history and political science, lawyers, and psychologists who already had doctor's degrees and were given fellowships for two or more years. It was hoped that some of them would become leaders in making psychology a basic part of these special sciences: and perhaps some of them yet will. So far they have done many excellent things, but not that.

I myself wrote Human Nature and the Social Order (1940), stating some of the facts of psychology which students of these special sciences, especially of Economics, Political Science, Law, and Philanthropy, seemed to me to need to know. This book may yet be used by such students, but so far it has not. Their neglect of it does not seem to be due to any distrust of me; for articles by me on topics strictly within the fields of economics, political science, and law have been accepted by the Quarterly Journal of Economics, the Harvard Business Review, the Public Administration Review, and the Columbia Law Review. The distrust seems to be of psychology.

It seemed to me probable that sociology would profit by studying the differences of communities in the same way that psychology studies the differences of individuals. Therefore I collected nearly 300 items of fact concerning each of 310 cities, studied their variations and intercorrelations, computed for each city three scores for the general goodness of life for good people for each city (G), for the personal qualities of its residents (P), and for their per capita income (I), and studied the causes of the differences among cities in G. The resulting book, Your City (1939), has been welcomed by leaders in many cities and used as an aid to community improvement, but has had little influence upon either research or teaching by sociologists. However, I still think that a college course in sociology may profitably include the measurement of individual differences among communities and the causation of these differences as revealed by suitable correlational methods.

It had long seemed to me that both the science and the teaching of language deserved more attention from psychology than they were receiving. I had begun with the humble task of counting the frequencies of occurrence of English words, publishing the facts for a ten-million count in 1921 and an extension of it in 1931. Dr. Irving Lorge and I brought out a greatly extended and improved count in 1944, and a count of meanings (A Semantic Count of English Words) in 1938. From 1937 on I published ten articles reporting work on euphony, semantics, and other features of language.

Apart from these three divagations I continued to work on learning, interests, and individual differences and their causes, especially heredity, as previously.

It should perhaps be noted that I have spent much time and thought on educational science proper, as shown in various monographs and articles, most of them factual.