Hull verses Tolman

The Differences and Debates between Early 20th CenturyPsychologists: Clark Lenard Hull verses Edward Chase Tolman

ByLadyAnn Gilreath

3868518 University of Minnesota

Psy 3993Professor Colin De Young

June 16, 2011

Key Words: Motivation, Drive, Latent Learning,Behavior Mechanism/System, and Information

Processing, Reinforcement

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OUTLINE

I. INTRODUCTION: Brief History of Psychology in the Early 20th Century

a. What is Psychology?b. What were the different types back then?

c. Clark Hull.d. Edward Tolman.e. Why should we still study themor care?

II. THEMES: Debates and Conflicts: Hull verses Tolman

a.Animal Behavioral Learning (Tolman, 1928-31).

b.Hypnosis: the Power of Suggestion(Hull, 1933).

c.Mathematical Mechanisms of Deductive Rote Learning (Hull, 1940).

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Hull verses Tolman

d.Essentials of Behavior, Hull’s Behavior System (Hull, 1951).

III. CONCLUSIONS: Outlooka. Circling or Progressing.b. Personal Opinion

Terms, Definitions and Who:

Psychology: The study of the mind and behavior as a science. It is not easy to pin one or two structured themes as the goals; psychology has since the early 20th century, spread into various sub-categories. However, its immediate goals are tounderstand the mental, conscious and un-conscious, cognitive, and social processes, which contribute to the attributes of human behavior, why, and how.

Behaviorism: After structuralism, functionalism, and psychoanalysis came in the middle of the 20th century, Behaviorism. Four great psychologists contributed to this field; John B. Watson, which was further heightened by Clark Leonard Hull, Edward Chase Tolman, and later B.F. Skinner with “Radical Behaviorism”.

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Structuralism: refers to the theory founded by Edward Titchener, (1867-1923), with a goal to describe the structure of the mind in terms of the most primitive elements of mental experience.

Functionalism: refers to the general psychology that considers mental life and behavior in terms ofactive adaptation to one’s environment. It providestheories that are really not testable in laboratorysettings. The theory focused on three things; the individual elements of consciousness, how they organize into more complex experiences, and how these mental phenomena correlated with physical events.

Psychoanalysis: Is a division of psychotherapy in which the developments of mental processes are analyzed in stages. They have defense mechanisms that are thought to be of the unconscious states ofmind. “There are 22 theoretical orientations of regarding human development. These various approaches are called psychoanalysis.” This was thework of the famous Sigmund Freud, from Austria during the late 1800’ and early 1900.

http://en.wikipedia.org/wiki/Psychoanalysis#1900.E2.80.931940s

INTRODUCTION

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Hull verses Tolman

What do we think when someone says or uses the term

psychology? I always think they are trying to use

reverse psychology and trick me somehow, many

others feel as I do, but there must be reasoning

behind our behavior and why we are thinking this

way. First, defining psychology is not easy there

are thousands of definitions. Psychology: The

study of the mind and behavior as a science. It is

not easy to pin one or two structured themes as the

goals; psychology has since the early 20th century,

spread into various sub-categories. However, its

immediate goals are to understand the mental,

conscious and un-conscious, cognitive, and social

processes, which contribute to the attributes of

human behavior, the underlying mechanisms that

cause it, why, and how. The earliest known

reference to the word psychology in English was by

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Steven Blankaart, in 1693, in “The Psychical Dictionary”.

This refers to “Anatomy, which treats of the body

and psychology, which treats the soul”.

http://en.wikipedia.org/wiki/Psychology. The great

German Psychologist William Wundt, is often thought

of as father of introducing psychological testing

in a laboratory setting, shifted psychology from a

humanities philosophical or religious approach, to

one of scientific approach; allowing for

quantitative measuring of behavior via several

methods.

Back when it was being considered for

scientific research there were several different

fields or spheres of psychology that were already

in existence. Amongst these were: Structuralism,

Functionalism, and Psychoanalysis. Now after these were,

(still thought of as today’s fields), Behaviorism,

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Humanism, Gestalt, Existentialism, Cognitivism, and the

Biopsychosocial Model, which started with research in

the early 20th century. From this we have gained

productive scientific information but also

inevitable diversities and conflicts between the

psychologists. (Refer to terms and definitions for

clarification of these).

Behaviorism: After structuralism,

functionalism, and psychoanalysis came in the

middle of the 20th century, Behaviorism. Four great

psychologists contributed to this field. First,

John B. Watson, which was further, heightened by

Clark Leonard Hull, Edward Chase Tolman, and later

B.F. Skinner with “Radical Behaviorism”.

In the early 20th century psychology was

preoccupied with establishing its identity as a

science.  It was obsessed with trying to separate

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itself from the nonscientific academic disciplines

of philosophy and religion moving closer to the

natural sciences, like physics, chemistry, and

biology.  Psychology tried to emulate the classic

sciences, especially physics, by establishing

"laws" of this and that, e.g., the law of effect,

the law of contiguity, the law of least effort, the

law of exercise, and all the Gestalt laws are

classic examples of this. For this paper, we will

examine the conflict/debates between two of these

great psychologists; that of, Clark Lenard Hull and

Edward Chase Tolman, from the early 20th century;

and compare it to views now in contemporary

psychology.

Clark Lenard Hull: Clark L. Hull: Was born May

24, 1884, in Akron, New York, becoming one of the

most influential psychologists, who dedicated his

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life to explain learning and motivation by

scientific laws of behavior. He attended a one-room

school for many years. He suffered from health

problems and contracted polio, which crippled him.

Health or financial issues were forever

interrupting his education. He originally started

out as a teacher but soon realized through the

questions posed by his students, that his own

education was severely lacking!

http://www.newworldencyclopedia.org/entry/

Clark_L._Hull

After pursuing a degree in mining engineering

receiving his bachelors and masters degree at the

University of Michigan; but, soon switched by

falling in love with the field of Psychology, and

later received his doctorate in Psychology in 1918

from the University of Wisconsin-Madison. For the

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next 10 years he continued on there and taught from

1918 – 1929. His doctoral research on

“Quantitative Aspects of the Evolution of Concepts”

was published in “Psychological Monographs”.

http://en.wikipedia.org/wiki/Clark_L._Hull

Clark Hull was handicapped and contracted polio

at the tender youthful t age of 24. His

contributions to the field of Psychology are well

known and established as scientific methodology.

Although his immediate work was on the

experimentation analytical study of the effects on tobacco

on behavioral efficiency, he also reviewed the current

literature on testing, beginning research on

hypnosis, but his life long emphasis was on the

development of objective methods for psychological

studies designed to determine the underlying

principles of behavior.

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http://en.wikipedia.org/wiki/Clark_L._Hull

He followed that up with his great research on

‘hypnosis’ and ‘suggestibility’ and wrote the book during

the year 1933 while at Yale University as a

research professor, where is stayed till 1952. It

is here that he developed his greatest

contributions in a laboratory setting, of the

theory: Systems of Behavior, basically using the

‘classical conditioning’ ideology of the great Russian

Physicist Ivan Pavlov. It was Pavlov that provoked

Hull into the reflex reactions and responses of

learning. Principles of Behavior was published in 1943.

His crowning achievements were in the Drive Theory and

the Reduction Theory.

The Drive Theory states; that human beings

experience biological and psychological needs; and

that much of human behavior occurs as an effort to

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satisfy those needs and reduce the potency of

biological or psychological drives.” These drives

include basic physical needs like thirst, hunger,

desire for sex, etc. and the psychological needs

like the need for companionship, comfort, security,

or the sense of belonging.

http://www.wisegeek.com/what-is-drive-theory.htm

Hull believed that much of our learning is due

to drive reduction. Human beings first recognize

the need to satisfy the drives by taking action to

fulfill the need, and then learn, through

behavioral conditioning, and how that need can be

satisfied in the future. Hull became a renowned

contributor and behaviorist to the field of

psychology. He died in new Haven Connecticut, on

May 10th, 1952.

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Edward Chase Tolman: was born on April 14,1886,

in Newton, Massachusetts. As a youngster he

graduated from Newton public schools in 1907 and

from the Massachusetts Institute of Technology in

1911. He then studied at Harvard for his graduate

study in the field Psychology.

He lived in an “upper class” socioeconomic

status; his father was the president of a

manufacturing company. He had a brother, Richard,

who was 5 years older than he, and both were

expected to follow in the family business. However,

they both decided to seek academic careers against

his father’s hopefulness. After high school

graduation that summer he took a course in

philosophy and psychology and decided that he was

not smart enough for the philosophy so he continued

in psychology. Then he enrolled at Harvard where a

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course in ethics taught by Ralph Barton Perry, as

well as readings of McDougall, led to his interest

in motivation.

http://www.muskingum.edu/~psych/psycweb/history/

tolman.htm

After his first year at Harvard, that summer he

traveled to Giessen, Germany actually to study for

his PhD in German, due to the fact that in this

time period all PhD examinations were done either

in German, French, or Russian. Here he received an

up close and personal introduction to Gestalt

psychology. He observed the worlds initial

reactions to this new academic ideology of Gestalt

psychology from Wolfgang Köhler, Max Wertheimer,

and the readings of Kurt Koffa. Also in this

timeframe were the behaviorist psychological ideas

of John B. Watson. Both these fields of psychology

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had an impact on Tolman. His following theories are

based from these two fields!

“Tolman studied laboratory techniques under

Hugo Munsterberg and Langfeld researching nonsense

syllable learning.”

http://www.muskingum.edu/~psych/psycweb/history/

tolman.htm

For his PhD he researched and did a study on

retroactive inhibition (Hilgard, 1987), and graduated in

1915. Sometime later in the fall of 1923, he

returned to Giessen, to pursue education in the

Gestalt psychology domain. He then taught at

Northwestern University for three years after

receiving his PhD. He felt his shortcomings were

being too self-conscious, inarticulate, and fearful

of his classes. He was considered a pacifist, and

his views disabled his employment during World War

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I. where he was called to the Dean for his anti-war

statements, which got published in a pacifist

student publication. So in 1918 he went to teach at

the University in California at Berkley, where he

stayed until 1954.

An interesting fact about Tolman was in his

passionate pursuit of truth led him to refuse to

sign the California Loyalty of Oath, 1949-50; a law that

the university tried to impose on their faculty to

comply with state law. Even though he advised his

peers to sign, the act was considered full of

courage where he gained much recognition for this!

His marriage was a very happy one. He died November

19, 1959 in California.

Why should we study these donations to

psychology of so long ago? Simply because they are

theories of learning; which guides new studies of a

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more complex nature; to actually dive deeper in the

underlying mechanisms of computational methods

explaining the new eras of behavior as they

progress. The more you learn the more you want to

investigate. As times move forward, the advancement

of many psychology fields come from the foundations

of the past psychology studies and constructs.

Without the past there could be no present or

future, apply this to the advancement of psychology

and you will know and understand the why.

Theme #1: Animal Behavioral Learning, (1928-1931).

To quickly outline the opposing forces between

Tolman and Hull let us start with Tolman with his

beliefs and experiments. Tolman was a champion of

Gestalt and adopted a theory of pattern. This sounds

very simple but has significant implications when

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identifying behavior both in human and animals, as

animals or humans have patterns they unconsciously

follow and learn through environmental cues, some

sort of mapping system of cognition, that Tolman

referred to as production of stimuli, sent and stored

to the sub-conscious. Tolman throughout his reign

was constantly tying to prove that animal behavior

was more complex than other psychologists believed.

In his book, “Psychology” (1929-31), he goes

through a systematic approach to verify this in his

well renound ‘RAT’ studies and experiments. Using

rats in mazes of different sizes and shapes, he

started his most simplistic experiment in which the

rat was to by deciding using free will, pattern-

wise discrimination between the mazes of an

equilateral triangle path from the irregular

pentagonal path of equal length (Brown, Tolman,

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Jones, 1928) (pg.3). The “free will learning” experiment

was conclusive that it landed about 50% for both

groups of rats, out of 30 rats: 15 went the

triangle way way, and 15 went the pentagonal way,

even with practice and training. Tolman himself

thought of learning as developing from bits of

knowledge and cognitions about the experiment and

how the organism related to it. This seriously

contrasted with Thorndike and Hull who thought of

learning as a strict stimulus-response connection

with reinforcement.

Next he investigated the genetics of learning ability

in rats, to discover the learning possibilities

through cognition (pg. 71-89). This is simply

nature verses nurture, to what degree does genetics

play or environment play in social context of

learning in maze efficiency?

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This was followed by examining the maze running

of how the role of reinforcement plays in difficult

maze running to a specific destination. This is the

key to “latent learning”; this describes learning in

the absence of reward (Baker, 1997).

Following this came the “insight” rat-learning

phase (Brown, Tolman, Jones 1930), (pg. 215-232).

With this he started changing the rate of incentive

or “drive” by not feeding the rats and letting them

get hungry. Hundreds of experiments were done in

different degrees of food deprivation as well as

timing and size they had to run, figure out which

way, and finally reach the goal, to find the food.

Many aspects of learning, hypothesizes, and

alternative theories came from this type of

experimenting. Using animals was at the heart of

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most of the historic psychology theories of

learning, and learning ability.

The rats did in fact learn when to turn right

in a 90-degree angle, or to go straight, or to

follow curves and stop points to cue the learning.

Continuing on there was what Tolman called a

“delay in reaction”, (Brown et. al., 1931)(pg307-318).

Rats cannot display this delay of reaction, as they

would not and could not stand still for the

reaction time to pass. This made for great

differences in the rats as some perform better than

others. However, they did many of this type of

experimenting with human children and got much

better results.

Tolman, finally, with his most prominent

experiment where there were 3 groups of rats, used

a complicated maze in a control setting. This

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experiment went on for 30 days, each day the first

group, G1, of rats ran the maze and when they got

to the end goal, found a pellet of food, (stimulus-

reward). The second group, or G2, of rats also ran

the maze but when the finished there was no pellet

of food. This group of rats actually went back to

the beginning much faster than group one who

lingered to see if any more food was forth coming.

The G3, or group 3, of rats ran the maze and like

the second group found no food. This was day one.

Measurements were taken for timing also to see

which group ran the maze faster. On day two, the

G1 ran the maze very fast, got the food, and then

went back. The G2 only a couple of rats ventured

out in to the maze and did not run in any sense of

the word, they strolled, never reaching the end

goal; but, they were not looking to cooperate, they

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were just “hanging-out” with no real purpose in

mind. The G3 of rats emulated the G2 much the same

way. What is not outwardly shown is that the maze

was simply nothing other than that, in other words,

there were no other stimulus cues as to which way

to the goal line, nothing that could be a signal to

them for timed future running. This went on just

that way for 10 strait days. On the 11th day, the G3

went to the end and found food. It took them a

while to mosey-on-down to reach the end but they

made it and found the stimulus-reward>>>food. On

the 12th day there was such a huge significant

change in the G3, they actually ran the maze faster

than G1 and remembered the maze so well that

Tolman’s theory of (S-S), stimulus-stimulus

connection, without reinforcement he claimed due to

recalling from the cognition of spatial production the

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mapping of the maze from the first time they ran

it, they just chose not to exert effort for

nothing.

What happened is the rats knew the maze from

the very first time they went through it; they

learned it! Even though they practiced several days

they had no real effort shown as to purpose of

entering the maze or going back to the starting

point. Once they had the new added stimulus of

food, they exerted major force to get to the goal

line before their peers did first! They recalled

the formation of the maze, which led Tolman to

believe that learning could be done with a

stimulus-stimulus connection and without

reinforcement!

Theme #2: Hypnosis, the Power of Suggestion, 1933

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In the book he wrote, “Hypnosis and Suggestibility”

in 1933, on the preface (pg. ix), Hull describes

how he got interested in the power of hypnosis.

Hull states that he was giving lectures to medical

students and had no answers to some of their

questions. However, the possibilities that came to

mind were profound, enough he could not resist the

impulse, for example: mental health guidance

attempting through a hypnotic pathway for partial

cure (suggestibility), enabling slower cognitive

abilities to better achievement and accuracy of

performance (hypnotic proposal), and the

possibility of recalling lost memories in amnesia

patients (awake under layers of sub-consciousness).

Hull decided to try the hypnosis hypotheses by

using what was then called principles, but is now

called postulates.

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Hull took two approaches: experimental and

clinical. He states the people “chosen” were normal

people as opposed to pathological persons, and were

picked at random. The desired end goals allegedly

were to be aware of principles and relationship,

rather than, treatments and cures. In this book

Hull acquiesces he enjoyed the thrilled excitement

of an occasional successful point, and to share

them with the world. Utilizing some of his trials

to prove pure science existed; which was very

controversial during the psychology-as-a-science

era.

The one thing that Hull proved or rather

disproved was that hypnosis was not a part of sleep.

He used a statistical and experimental analysis to

approach this concept conclusive that is was in no

way a part of sleep or connected.

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The main results from this on-going study

where; it was thought and predicted that hypnosis

could be heightened for better cognitive processes.

That through hypnotic suggestion, the underlying

forces subconsciously alter cognitive aspects to a

higher state ultimately for improved for sensation

and cognitive capacity. He thought through hypnosis

he could get amnesia patients to recall things they

had forgotten, in a traumatic event, or things we

put so far under due to hurt, embarrassment, shame,

or trauma. (For example: hysterical amnesia: where

something so traumatic causes severe distress,

acute anxiety, and impairment of daily

functioning). These were extravagant claims but

none-the-less he was well known for his studies in

this area. It was also hypothesized that hypnosis

could “induce” (word quoted); moderate increases in

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certain physical abilities changing the sensation

to higher plains from a biological perspective.

In the end, many contributions to the field of

hypnosis, for example: “comparisons of capacities

in a non-hypnotic state with those of a hypnotic

state are considered still valid today”.

http://www.ncbi.nlm.nih.gov/pubmed/1543147

Theme #3: Mathematical Mechanisms of Deductive Rote Learning (Hull, 1940). A study in scientific methodology.

(NOTE: The other authors of this book are as follows: Carl I. Hovland, Robert T. Ross, Marshal Hall, Donald T. Perkins, and Fredric B. Fitch, should be given due credit).

Hull set out to devise a ‘system of behavior’

using mathematics; he created a set of postulates,

theorems, and corollaries. It was the Institute of

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Human Relations at Yale University, which assisted

in furnishing the making of this book to further

convince the outside world, psychology could be

thought of as a natural science!

In this book he describes that the mathematics

he designed were simply symbols to use to learn the

types of behavior. They are some symbols known to

us an others not so well known! It was a work of

dedication and the use of evolutionary psychology

(much of survival of the fittest) that led to the

18 Postulates created. Hull claims that the

postulates are assumptions and basically have two

sides to them. However, at the time of using any

certain postulate, it was only one of the sides

would be scrutinized under active discussion.

(Hull, et. al, 1949) (Pg. 2). “The postulates that

are usually, and properly, under active discussion

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in a scientific system are those which purport the

natural laws. Including in these postulates are

Newton’s three postulates of laws of motion.” (Hull,

et. al. 1940) (Pg. 45). In the works of logic,

three criteria are ordinarily given for the

postulates of any logical system. They are that

the postulates shall be 1) As few as possible, 2)

Consistent with each other, and 3) Sufficient to

mediate the deduction, the theorems, and of all

relevant facts. (PG 65). In actuality, Hermann

Ebbinghaus began the precise experimental

investigation of the psychology of rote learning,

over half a century ago.

Looking at the definition of rote learning: “Rote

learning is a learning technique, which focuses on

memorization. The major practice in rote learning

is learning by repetition.” The basic idea is that

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the more one is exposed to the word, event, or

situation, will be able to recall it faster.

http://en.wikipedia.org/wiki/Rote_learning

Some examples of rote learning are the periodic

table for chemistry, phonics in reading,

multiplication tables, anatomy for medical

students, cases or statutes for lawyers, basic

formulas in any science! For the best rote-learning

example, is that of studying for an exam the night

before it is given, which is colloquially termed as

“cramming”. In the end of the postulates are

followed by his theorems, which number to 55 of

them. This work of Hull explained may behaviors But

for this paper we are going to concentrate on one

formula that is his greatest contribution, that of

Drive Reduction Theory.

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Theme #4: Essentials of Behavior, (Hull,

1951)

Hull’s “Drive Reduction Theory” is the compiled

works of Pavlov, Darwin, Thorndike, and Tolman with

a touch of Newtonian physics. Hull is best known

for his Drive Reduction Theory and is postulated to

be the “responses” to “drives”, normal things like

thirst, hunger, sex drive, feeling cold, etc.

Now when the goal of the drive is reduced (ie.

Thirsty: the drive, drinking water, the response;

thus, drive is reduced by the response of the drinking

of the water!)

In math, he wrote out his drive reduction theory as

the action potential for the motivation performing

actions to reduce drives. Followed by lowering the

innate need, which causes the drive, which causes

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motivation to respond to that drive via a stimulus-

response reduction!

“Hull’s model is complicated only in symbolism

otherwise it is extraordinarily simple to

understand! In biological terms: Organisms suffer

deprivation. Deprivation creates needs. Needs

activate drives. Drives activate behavior. Behavior

is goal directed. Achieving the goal has survival

value.” This is hierarchy of innate drives for

simple survival as a species. Evolution states that

the first instinct is the survival instinct! (flight or

fight).

http://en.wikipedia.org/wiki/Clark_L._Hull

In this model came forth the formula for the

motivational instinct to activate behavior:

sEr = (sHr x D x K x V)

- (sIr + Ir) +/- sOr

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“Habit strength, sHr, is determined by the number

of reinforces(how many times in succession the food

is there so keep trying your hardest to be first).

Drive strength, D, is measured by the hours of

deprivation of a need (keeping rats hungry with out

the stimulus of food), K, is the incentive value of

a stimulus (stimulus= food), and V (what

measurement of performance or initiative is tried

or risked for the successful reaching of the

stimulus {food}) is a measure of the

connectiveness. Inhibitory strength, sIr, is the

number of non-reinforces (when the food is not at

the goal). Reactive inhibition, Ir, is when the

organism has to work hard for a reward and becomes

fatigued (when the food is held for certain periods

of time in length; for example, days then suddenly

food.). The last variable in his formula is sOr,

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which accounts for random error. Hull believed that

this formula could account for most behavior. Hull

was more of a mechanical psychologist. It might

have been possible if he had had more time to build

the first computer or robot. He looked at things as

components to a whole, holistic style if you musty

say; yet it was Tolman who found Gestalt Psychology

and mastered it and is well known for his Gestalt

styles.

CONCLUSION;

The difference between Hull vs Tolman is the

difference between conditioning mechanism vs

information processor, molecular analysis vs molar

synthesis, elementalism vs holism, reinforcement

theory vs expectancy learning, and mindless habit

vs cognitive understanding.  Tolman was a champion

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of Gestalt and cognitive psychology, whereas Hull

was more of a biomechanical theorist.

DIFFERENCES and CONTRIBUTIONS

HULL’s

The biggest contribution that each made to the

field was:  Hull showed how it was possible to

bring rigorous theoretical analysis to bear on the

problems of psychology and to have theory guide the

building of a machine (in the abstract or in

reality) that could learn.  That is to say, his

approach was basically the notion that if you could

engineer a machine or a computational system that

behaved exactly the way people behaves, then that

machine or computational process was a legitimate

model of human behavior.  If he were young and

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alive today, he would be an artificial intelligence

computer engineer or maybe a robot builder.

TOLMAN’s

Tolman's biggest contribution was to keep the

behaviorists from over simplifying things by

constantly demonstrating that animal behavior was

much more complex and intelligent than they

thought.  

IN THE END:

In the end, both of their approaches

succumbed to massive and impractical

complexity and vague hypothetical

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abstractions that got them running around in

circles rather than progressing.  Too bad

they didn't have computers to keep them

grounded.

(NOTE: They were brilliant, and a pleasure to

research!)

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