About five feet five inches (1.65 m) in height, Ben Bloom was not a very large man, but his
physical stature in no way reflected his presence in a room or the stature he achieved in the
field of education. It was, I confess, a kind of anomaly to see someone who had few
physically imposing qualities carry so much weight in a conversation and with so much of an
aura.
Benjamin S. Bloom was born on 21 February 1913 in Lansford, Pennsylvania, and
died on 13 September 1999. He received a bachelor’s and master’s degree from Pennsylvania
State University in 1935 and a Ph.D. in Education from the University of Chicago in March
1942. He became a staff member of the Board of Examinations at the University of Chicago
in 1940 and served in that capacity until 1943, at which time he became university examiner,
a position he held until 1959.
His initial appointment as an instructor in the Department of Education at the
University of Chicago began in 1944 and he was eventually appointed Charles H. Swift
Distinguished Service Professor in 1970. He served as educational adviser to the
governments of Israel, India and numerous other nations. These are some of the facts
pertaining to his life and career. To know the man and his work, however, we must delve into
what he stood for and what he accomplished as a teacher, a scholar and a researcher in the
field of education. That is the story I would like to tell.
Bloom as a teacher
I had my first contact with Ben Bloom as a student in the Department of Education at the
University of Chicago. He was one of my teachers. The course, and I remember it quite well,
was entitled ‘Education as a Field of Study’. Our aim in that course was to try to understand
the kinds of questions that might be asked about the field of education and to explore the
various ways in which those questions might be answered. It was a mixture of the conceptual
analysis of a complex concept and an introduction to the forms of inquiry that would result in
a research project. One aspect of the course focused on the use of statistics and the
calculation of probability. The approach that Bloom took was to help us understand
probability experientially. Unlike most instructors, who would be inclined to provide a
theoretical explanation of the meaning of probability, Bloom had each of us toss coins and
record the number of heads and tails produced in a number of trials. He then had the class
combine their respective ‘scores’, which of course yielded a relatively smooth bell-shaped
curve describing the distribution of occasions on which heads or tails appeared.
His willingness to devote the time in a graduate class to the actual production of an
event in order to increase the meaningfulness of the idea of probability was emblematic of
what always seemed to me to be a kind of hard-nosed progressivism that characterized his
orientation to education and especially to the assessment of the educational consequences he
thought important.
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Bloom’s strength as a teacher was not due to the fact that he was the most articulate
on the faculty at Chicago at the time; he was not. It was not because he necessarily invented
the most creative learning activities that graduate students might engage in; he did not. What
Bloom had to offer his students was a model of an inquiring scholar, someone who embraced
the idea that education as a process was an effort to realize human potential, indeed, even
more, it was an effort designed to make potential possible. Education was an exercise in
optimism.
Bloom’s commitment to the possibilities of education provided for many of us who
studied with him a kind of inspiration. He was, as I have indicated, an optimist, but an
optimist who looked to the facts and who designed the studies to give substance to his
aspirations.
I do not think I will ever forget being in a class of his in which the doctoral students
enrolled were asked to present proposals for their dissertations or to describe pilot studies
they had completed in preparation for their dissertation research. The weeks passed and it
was my turn to present. My dissertation was to focus on the measurement of types of
creativity displayed in two- and three-dimensional artwork made by children aged 10 and 11.
The criteria for identifying each of the four types of creativity I had conceptualized were both
complex and subtle; the tasks confronting the judges were to make judgements on subtle but
important aspects of the creative features of the students’ artwork. Alas, the inter-judge
correlations turned out to be in the forties and there were some snickers from my peers when
I put these coefficients on the blackboard. Bloom was slightly irritated by the responses of
my fellow students and proceeded to the blackboard to show to my surprise and theirs how
significant such correlations were in the light of the complexity of the tasks the judges were
asked to perform. He taught me in that demonstration the importance of supporting students
in difficult times and of putting statistics in context. How one interprets a set of numbers
depends not only on matters of measurement but also on the characteristics of the situation
from which those numbers were derived. That was a lesson I do not think I will ever forget.
Another feature of Ben Bloom’s pedagogy most often emerged in one-to-one
conversations in his office on the third floor of Judd Hall on the campus of the University of
Chicago. His office was not an aesthetic delight. It had one wonderful black and white
photograph of his mentor, Ralph W. Tyler, hanging on the wall. The rest of the office was
strewn with books, papers, journal articles, and a sundry array of this and that having neither
particular rhyme nor reason as far as I could tell. But it also had a large chalkboard, and it
was in conversations on a one-to-one basis with Ben Bloom that one could experience his
obvious pleasure in illustrating on the blackboard relationships that he expected to find or had
already found in research. In these conversations the excitement of research-oriented inquiry
was made palpable. It was clear that he was in love with the process of finding out, and
finding out is what I think he did best.
The cognitive taxonomy
One of Bloom’s great talents was having a nose for what is significant. His most important
initial work focused on what might be called ‘the operationalization of educational
objectives’. As I have mentioned, Ralph W. Tyler was his mentor. When Bloom came to
Chicago he worked with Tyler in the examiner’s office and directed his attention to the
development of specifications through which educational objectives could be organized
according to their cognitive complexity. If such an organization or hierarchy could be
developed, university examiners might have a more reliable procedure for assessing students
and the outcomes of educational practice. What resulted from this work is Taxonomy of
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educational objectives: Handbook 1, the cognitive domain (Bloom et al., 1956), a publication
that has been used throughout the world to assist in the preparation of evaluation materials.
The cognitive taxonomy is predicated on the idea that cognitive operations can be
ordered into six increasingly complex levels. What is taxonomic about the taxonomy is that
each subsequent level depends upon the student’s ability to perform at the level or levels that
precede it. For example, the ability to evaluate—the highest level in the cognitive
taxonomy—is predicated on the assumption that for the student to be able to evaluate, he or
she would need to have the necessary information, understand the information he or she had,
be able to apply it, be able to analyse it, synthesize it and then eventually evaluate it. The
taxonomy was no mere classification scheme. It was an effort to hierarchically order
cognitive processes.
One of the consequences of the categories in the taxonomy is that they not only serve
as means through which evaluation tasks could be formulated, but also provide a framework
for the formulation of the objectives themselves. Bloom was interested in providing a useful
practical tool that was congruent with what was understood at that time about the features of
the higher mental processes.
The publication of the cognitive taxonomy was followed by the publication of the
affective taxonomy. Bloom’s work was a signal contribution to mapping the terrain that
educators were interested in developing.
Bloom’s contributions to education extended well beyond the taxonomy. He was
fundamentally interested in thinking and its development. His work with Broder (Bloom &
Broder, 1958) on the study of the thought processes of college students was another
innovative and significant effort to get into the heads of students through a process of
stimulated recall and think aloud techniques. What Bloom wanted to reveal was what
students were thinking about when teachers were teaching, because he recognized that it was
what students were experiencing that ultimately mattered. The use of think aloud protocols
provided an important basis for gaining insight into the black box.
Mastery learning
The features that characterize Ben Bloom’s scholarship are several. First, as I have indicated,
he was interested in understanding the ways in which cognition functions and, more
important, how high-level forms of thinking can be promoted. Second, he had an abiding
faith in the power of the environment to influence the performance of individuals. He was no
genetically oriented determinist. His convictions about environmental influences led,
ultimately, to the impact that his work had in establishing the Head Start Program in the
United States. He was invited to testify to the Congress of the United States about the
importance of the first four years of the child’s life as the critical time to promote cognitive
development. His testimony had an impact. Third, Bloom believed that not only was the
environment importan