Copyright
Daniel Starch.

Educational psychology online

. (page 7 of 41)
Online LibraryDaniel StarchEducational psychology → online text (page 7 of 41)
Font size
QR-code for this ebook


Grade


Grade




Rank


Rank


Rank


Rank


Rank


Rank


3


72.3 9


85-1 5


82.2 3


80.7 5


76.7 8


77.9 8


5 '


7.S-I 7


76.1 9


73-2 9


74.6 9


75-3 9


76.1 9


4


So. 2 3


89. 1 I


86.7 I


83.6 I


84.6 I


84.0 I


6


80.4 2


85 9 3


81. 1 s


81.6 4


78.6 6


78.56


2


77-4 5


78.5 7


74.4 8


76.1 7


79-3 4


78.7 5


4


73.68


80.8 6


76.1 7


76.0 8


78.6 6


78.2 7


,S


77.6 4


86.6 2


84.4 2


83.2 2


83.8 2


83.8 2


3


76.1 4


78.4 8


80.5 6


80.0 6


78.6 6


79.6 4


3


Si. 8 I


855 4


82 I 4


82.5 3


Si. 6 3


81.9 3



"There is no evidence, at least from these figures, for the notion that
special abilities in certain studies run in families. Mental traits running
in families are very likely more specialized than abilities in school studies
which involve large groups of mental functions. The children of any
given family are on the average equally good or equally poor in all studies,
Ability in school work is apparently inherited to the same extent as
physical features since the coefficients of correlation for children of the
same parents are approximately the same for both physical and mental
traits." (Starch, '15, pp. 609-610.)

Schuster and Elderton ('07) calculated the resemblance in
scholarship between brother and brother and between father and
son among the Oxford honor men and found a coefficient of correla-
tion of .40 for the former and .31 for the latter. Miss Elderton
further determined the correlations between cousins from records of
about 300 families and found a coefficient of .27.

Miss Emily S. Dexter ^ made a study of the scholarship records of
185 pairs of brothers, sisters, brothers and sisters, graduates of the
University of Wisconsin, and of 69 similar pairs who were gradu-
ates of the high school at Ashland, Wisconsin, She reports the
following coefiicients:

^ The study was carried out under the direction of Professor Henmon and reported
in a thesis in the library of the University of Wisconsin, 1915.



J



THE INHERITANCE OF MENTAL TRAITS



85



TABLE 20





Number
OF Pairs


General
Scholar-
ship IN
ALL Sub-
jects


English


Lan-
guage


Mathe-
matics


History


Science


University:

All pairs

Bro. and bro. . .

Sis. and sis. . . .

Bro. and sis. . . .
High School :

All pairs

Bro. and bro. . .

Sis. and sis. . . .

Bro. and sis. . . .


1S5
44
71
66

60
10
26
-3


.69

•47
53
62

.64
■38
39
36


.64

.58


•63


•55


.62
•63


.60
.61



Miss Dexter concludes "that inheritance, to a much greater extent
than training is responsible for the degree of resemblance found."

"If it were largely training, we would expect to find the resemblance
greater between brother and brother, and sister and sister, than between
brother and sister, but such is not the case. In the high school the cor-
relations for the three groups are much the same, but, as has been pointed
out, that may be due to a great extent to chance, for the groups are small.
However, in the case of the university, where the groups average nearly
three times as large as in the other school, we find the resemblance be-
tween brother and sister to be greater than between brother and brother,
or sister and sister.

"Again, there is the question as to specialized abilities, and also that of
general mental ability rather than specialized abilities as a basis of ex-
planation for the close resemblance found. Thorndike, as has been said,
finds that heredity is highly specialized. This study, however, seems to
show a stronger tendency toward general mental ability, if by that we
mean approximately equal ability in all subjects. It seems, also, to give
almost no evidence of alternate inheritance; that is, of one individual's
inheriting ability in one line while his brother inherits ability in another.
In other words, a student who is above the average, either of his family
or of the school, in one subject, is usually also above in most, and in many
cases all, other subjects."



Similarities of Twins in Special Mental Traits. The two prin-
cipal investigations on, this phase of mental heredity were made by
Galton and Thorndike. Galton made a general comparison of two
groups of twins, one group of 35 pairs, which were reported as being
very similar, in fact so similar that they were frequently reported



86 EDUCATIONAL PSYCHOLOGY

as indistinguishable, and another group of twenty pairs of dis-
tinctly dissimilar twins. The conclusion formulated was to the
effect that the former twins remained very similar all through
life in spite of different environments, while the latter twins re-
mained different all through life in spite of similar environments.
Concerning certain of the twins Gal ton reports:

"i. One parent says: 'They have had exactly the same nurture from
their birth up to the present time; they are both perfectly healthy and
strong, yet they are otherwise as dissimilar as two boys could be, phys-
ically, mentally, and in their emotional nature.'

"2. 'I can answer most decidedly that the twins have been perfectly
dissimilar in character, habits, and likeness from the moment of their
birth to the present time, though they were nursed by the same woman,
went to school together, and were never separated till the age of fifteen.'

"3. 'They have never been separated, never the least differently
treated in food, clothing, or education; both teethed at the same time,
both had measles, whooping-cough, and scarlatina at the same time, and
neither had any other serious illness. Both are and have been exceed-
ingly healthy and have good abilities, yet they differ as much from each
other in mental cast as any of my family differ from another.'

"5. 'They were never alike either in body or mind and their dissim-
ilarity increases daily. The external influences have been identical; they
have never been separated.'

"9. 'The home-training and influence were precisely the same, and
therefore I consider the dissimilarity to be accounted for almost entirely
by innate disposition and by causes over which we have no control.'"
('83, p. 170, Everyman's Library Edition.)

Galton's general impression of his results is as follows:

"We may, therefore, broadly conclude that the only circumstance,
within the range of those by which persons of similar conditions of life
are affected, that is capable of producing a marked effect on the char-
acter of adults, is illness or some accident that causes physical infirm-
ity. . . . The impression that all this leaves on the mind is one of some
wonder whether nurture can do anything at all, beyond giving instruc-
tion and professional training. There is no escape from the conclusion
that nature prevails enormously over nurture when the differences of
nurture do not exceed what is commonly to be found among persons of
the same rank of society and in the same country." ('83, pp. 168 and 172.)



Thorndike's investigation ('05) was made by more accurate
methods. He applied the tests, mentioned in the following table
to 50 pairs of twins and found the following correlations:



)le, t|

J



THE INHERITANCE OF MENTAL TRAITS



87



In the A-test R—

In the a-t cand r-e test R —

In the misspelled word test R —

In addition R —

In multiplication R —

In the opposites test R —



"If now these resemblances are due to the fact that the two members
of any twin pair are treated alike at home, have the same parental
models, attend the same school and are subject in general to closely
similar environments, then (i) twins should, to the age of leaving home,
grow more and more alike, and in our measurements the twins 13 and
14 years old should be much more alike than those 9 and 10 years old.
Again (2), if similarity in training is the cause of similarity in mental
traits, ordinary fraternal pairs not over four or five years in age should
show a resemblance somewhat nearly as great as twin pairs, for the
home and school conditions of the former will not be much less similar
than those of a pair of the latter. Again (3) if training is the cause,
twins should show a greater resemblance in the case of traits much sub-
ject to training, such as ability in addition or in multiplication, than in
traits less subject to training, such as quickness in marking off the A's on a
sheet of printed capitals, or in writing the opposites of words.

"On the other hand (i) the nearer the resemblance of young twins
comes to equalling that of old, (2) the greater the superiority of twin
resemblance to ordinary fraternal resemblance is, and (3) the nearer twin
resemblance in relatively untrained capacities comes to equalling that in
capacities at which the home and school direct their attention, the more
must the resemblances found be attributed to inborn traits.

"The older twins show no closer resemblance than the younger twins,
and the chances are surely four to one that with an infinite number of
twins tested, the 12-14 year-olds would not show a resemblance .15
greater than the 9-1 1 year-olds. The facts are: (Thorndike '14, III,
pp. 248-249).

TABLE 21
The resemblances of young and old twins compared.



Twins, 12-14



1. A-test

2. a-t and r-e tests. . . .

3. Misspelled word test

4. Addition

5. Multiplication

6. Opposites

Averages




88 EDUCATIONAL TSYCHOLOGY

The Influence of Uniform Environment Upon Different Original
Abilities. All studies cited thus far have attempted to measure
the amount of similarity in related persons as compared with un-
related individuals on the assumption that the environment was
roughly constant for all, that whatever resemblances existed be-
tween pairs of brothers and sisters or between other types of rel-
atives greater than that between any pairs of persons selected by
chance from the population at large, is considered to represent
the actual amount of similarity in the original inherited natures of
the individuals springing from the same ancestry. The problem
may, however, be pursued further from a different angle, namely, by
specific control of the environment or some portion of it. Thus it is
possible to keep some particular part of the environment uniform
for a group of persons of widely different abilities and to measure
to what extent the original differences remain constant, increase,
or decrease. If the differences remain constant, or increase, the in-
ference would be that the ultimate differences of achievement would
be primarily due to the inherited differences of capacities. If the
differences decrease materially and finally disappear, the original
differences would be mainly due to the effect of environment and
opportunity.

A number of such experiments have been carried out. An in-
vestigation made by the writer ('ii) in which S persons multiplied
mentally 50 3-place numbers by a i-place number each day for
14 successive days showed the following amounts of improvement:

TABLE 22



numder of
Examples in
1st 10 MiN.



Number of
Examples in
Last 10 Min.



Gain in No. of
Examples



Per Cent
Gain



Three best jiersons . .
Three poorest i)crsons



39



84
51



45
26



115
104



Hence, both the greatest absolute and the greatest relative gain
was made by the group with the highest initial records.

Similar results have been found in the practice experiments of
substituting numbers for letters as described in the author's Ex-
periments in Educational Psychology, Chapter X. The follow-
ing table gives the highest five and the lowest five records from
among twenty persons. Each person practiced 120 minutes.



i



THE INHERITANCE OF MENTAL TRAITS



89



TABLE 23
Average number of letters transcribed.



First 5 Min.



Last 5 Min.



Gain



Initial highest five persons.
Initial lowest five persons .



139
100



310
239



171
139



Again the largest gain was made by the group having the greatest
initial ability.

Results pointing in the same direction have been obtained by
Thorndike, Whitley, and others. For example, Thorndike ('lo)
found in the case of practice of nineteen persons in adding, the fol-
lowing results:

TABLE 24

The effect of equal amounts of practice upon individual differences in column
addition of one-place numbers. After Thorndike ('10).











Average Time




Average Number of Additions per 5 Minutes


Spent in Practice




Corrected for Errors


from Mid-point of










First Test to Mid-
point OF Last Test












First Test


Last Test


Gain


(in Minutes)


Initially highest 6 in-










dividuals


297


437


140


40


Initially next highest










6 individuals


234


345


III


49


Initially lowest 7 in-










dividuals


167 —


220 +


54


46







The statistical studies of scholastic histories of pupils through
various periods of school life, which were discussed in a preceding
chapter under the heading of correlations of abilities at different
times of life in the same individual, all tend to corroborate the ex-
perimental facts here presented. The scholastic records show to a
remarkable extent the uniformity with which each individual main-
tains his position throughout his educational career. A very in-
teresting tabulation was made by L. J. Coubal and E. VanLande-
gend ^ to show the progress made by pupils in grades 4, 5, and 6
in one school in the four fundamental operations in arithmetic.
Progress was measured by the Courtis tests. Series B, month by

^ Under the direction of Professor Henmon, and reported in two theses in the library
of the University of Wisconsin, 1917.



90



EDUCATIONAL PSYCHOLOGY



month through an entire year. The records in the four opera-
tions for each pupil were combined into a single score. Figures 32,



50



40



30



20



10















,












/




— -— .










- /y




_^,






/


=^




>^


/




=r^


"^^


-■










/■





.Sept. Oct. Nov. Dec. Jan. Feb. March April May,
Fig. 32. — Progress in the four fundamental operations in arithmetic as
measured by the Courtis tests, Series B, given at monthly intervals. The
heavy continuous line represents all the pupils of the 4th grade. The four broken
lines represent these pupils divided into quartiles.
70



60



50



40



30



20



10





























>




^
















/^'


-s






^.






y








4


■:>"


'">>..


^


/
/




\
\
\

\




■■=^'^.


^-^


— ■





























Sept. Oct. Nov. Dec. Jan. Feb. March April May
Fig. 2>7>- — Same as Fig. 32, for the 5th grade. Pupils divided into three groups
instead of four.

33, and 34 give the curves of progress for the respective grades.
The pupils in each grade were divided into groups according to
their final performance. Thus the pupils in grade 4 were divided



1



THE INHERITANCE OF MENTAL TRAITS



91



into four groups while those in the other grades were divided into
three groups. The results reveal the significant fact that the best
groups in each grade made the greatest progress, the poorest groups
made the least progress and the intermediate groups made average
progress. The graphs for the various groups in any grade gradu-
ally spread apart during the course of the year, indicating that the
differences increase rather than decrease or remain constant. The
more gifted pupils profit more by their school work than the less
gifted.

All experimental results point in the direction that practice does

not equalize abilities; in fact, equal practice tends to increase differ-

70



60



60



40



30



20



10



Sept. Oct. Nov. Dec. Jan. Feb. March April May
Fig. 34. — Same as Figs. 32 and S3, for <Jtli grade.

ences in achievement and skill rather than to decrease them. The
more gifted individuals profit more, both relatively and absolutely,
than the less gifted. This experimental fact is one of the most pro-
found bits of evidence regarding the whole problem of heredity and
environment. The talented men not only start with greater initial
capacities but seem also to be capable of more intense application
and more zealous desire to improve. "To him that hath shall be
given" is psychologically true in the sphere of intellectual training
as well as in the sphere of morality and religion. The man with
ten intellectual talents will acquire far more than the man with one
talent. If we may generalize for life as a whole, equal opportunities















y


.. - '




























^,^''''


/




"^^,








^■^

^




^.^


V.






— ^"""""




■s.-::^ -




^~~-


yf


- ^^


/
/
/






_..


^-^


~~~-


^^



























92 EDUCATIONAL PSYCHOLOGY

for all do not produce equal abilities in all. Men may be born free
politically, but they are not born equal mentally; they may be
born equal in opportunities in a democratic society, but they cer-
tainly are not equal in their ultimate achievements in life.

Influence of Different Environments upon Various Original
Abilities. Extensive inquiries into the effects of various environ-
mental conditions upon the native ability of human beings have
been made in other fields besides the experimental one which has
been surveyed. Such investigation as the study made by Dr.
Rice ('97 and '02) upon the effects of various factors in school life
upon the attainments in spelling and in arithmetic, the studies of
places of birth of American men of science made by Cattell ('06),
or the study of the places of birth of eminent men of letters made
by Odin, and similar investigations by De CandoUe ('73), Jacoby
('81), and Ellis, have been extensively referred to as bearing upon
the problem of environmental forces in their interplay with heredi-
tary capacities. The real significance and argumentative weight of
such data seem to the writer to be uncertain and duplex in their
meaning. Cattell, for example, has pointed out that the number of
eminent scientific men born about 1S60 in Massachusetts per one
million population was very much greater than the number of
eminent scientific men born in proportion to population in other
states. To cite a few instances, he has computed that per one
million population there were born eminent scientists as follows in
various states:

Mass 108.8

Conn 86. 9

R.I 25.6

N. Y 17.0

Wis 45 . o

III 24.0

Ala 2.0

Miss I . o

Similar figures are given for other states, and the inference made
by Cattell is that the environment of Massachusetts and similar
states has been much more conducive to the development of scien-
tific men and that the number of such men could be determined
practically by the control of the proper educational stimuli.

Odin, in his study of 5,233 noted French men of letters living
during the period 1400 to 1830, found the following distribution
according to places of birth:



THE INHERITANCE OF MENTAL TRAITS 93

1,229 born in Paris

2.264 " " other large cities

1.265 " " small cities

93 " " country districts

From this it has been inferred that if France as a whole had
been as fertile as Paris in the production of eminent men of letters
there would have been approximately 54,000 great men of letters
instead of less than 6,000. The difficulty, however, with both
studies is that Paris and Massachusetts have been more productive
of eminent men not necessarily on account of better educational
and social environment, but possibly also because of the fact that
eminent men of letters and science have by virtue of the location
in them of educational institutions, scientific and other intellectual
centers, necessarily been attracted to these places, and conse-
quently their children were bom in these localities. The facts as
such may actually be used in the support of heredity as against
enviromnent as much as they have been used in support of en-
vironment as against heredity.

Likewise, the study of Rice with regard to the factors affecting
efficiency in school subjects is uncertain. Rice, on the basis of
extensive tests in spelling and arithmetic in various parts of the
country, arrived at the general opinion that practically all external
conditions of home and school such as foreign or American parent-
age, home study, methods of teaching, size of class, and time
devoted to study, made practically no difference whatever in the
ultimate achievement of the pupils, and the implication is made
that the final efficiency depends primarily upon heredity. The
obvious uncertainty of such data as these is that while the facts
in toto may imply such a situation, it is also quite certain that such
a massing of data in this manner obliterates the effect of individual
factors. Favorable conditions may be offset by unfavorable condi-
tions and thus obscure the entire situation. To infer that good
teaching and poor teaching make no difference in the ultimate
results obtained, or that the amount of time given to study makes
no difference in results, are conclusions that are quite likely to be
unsound. The reason for the inference drawn by Rice is probably
the fact that good teaching in some schools may be accompanied
by other factors which tend to counteract its effect, whereas poor
methods of teaching in other schools may be accompanied by
favorable or unfavorable circumstances in other respects. The
massing together of returns from many schools is bound to ob-



94 EDUCATIONAL PSYCHOLOGY

literate the effects of the individual conditions. The only certain
way to ascertain the effectiveness of one factor or another would
be to control all conditions, or to be able to allow for them definitely,
with the exception of the one factor whose efficacy is to be deter-
mined. Thus in order to determine whether or not the different
methods of teaching a given subject make a difference, it would be
necessary to take a class of pupils in a given school and divide it up
into two or more groups on the basis of equal initial capacities and
to have each class taught, preferably by the same teacher and un-
der the same general circumstances, by a different method. Then at
stated intervals the two groups should be compared by reliable
measures. In this manner definite results could be obtained as
to the effectiveness of the various methods, conditions, or amounts
of time devoted to a subject. Consequently, Rice's figures as they
stand are of little worth so far as proving the forcefulness of dif-
ferent environmental factors in the production of results is con-
cerned.

A similar criticism applies to such studies as that made by Spill-
man with regard to the place of birth of various men prominent
in public and business life, such as presidents of the United States,
governors, and railroad presidents. Spillman ('09) has pointed
out, for example, that 23 of the first 25 presidents of the United
States were born in the country, that 41 out of 45 governors, and
47 out of 62 cabinet officers were born in the country. It is unsafe
to argue that because a large percentage of the presidents of the
United States or other prominent persons were born and reared
in rural districts, that country life is more productive of ability
and ambition. To argue with any certainty on the basis of such
facts, it is necessary to know the ancestral antecedents of the
persons springing from various localities and sections of the popu-
lation.

General Interpretation. The general impression from all ex-
perimental, statistical, and historical material thus far accumulated
on the problems of mental heredity would seem to be somewhat
as follows: Barring paupers, invalids, and those suffering from
want of food and shelter due to conditions beyond their personal
control, and referring to all others living in the same community
at the same time, the ultimate achievement of any given individual
is due to his original ability, probably to the extent of 60 to 90%,
and to actual differences in opportunity or external circumstances
only to the extent of 10 to 40%.



THE INHERITANCE OF MENTAL TRAITS 95

The facts of heredity bear down so heavily that the impression
gained of the large part played by it leads one almost to a fatalistic
philosophy. One is almost inclined to believe that persons become
what they do largely on account of their hereditary capacities, and
that they are not in the least responsible for their own outcome;
that if a person is born with great capacities he will achieve high



Online LibraryDaniel StarchEducational psychology → online text (page 7 of 41)