Giving Differences From Memory

PROCEDURE. Say: "_What is the difference between a fly and a

butterfly?_" If the child does not seem to understand, say: "_You know

flies, do you not? You have seen flies? And you know the butterflies!

Now, tell me the difference between a fly and a butterfly._" Proceed in

the same way with _stone and egg_, and _wood and glass_. A little

coaxing is sometimes necessary to secure a response, but supplementary

questions a
d suggestions of every kind are to be avoided. For example,

it would not be permissible for the examiner to say: "_Which is larger,

a fly or a butterfly?_" This would give the child his cue and he would

immediately answer, "A butterfly." The child must be left to find a

difference by himself. Sometimes a difference is given, but without any

indication as to its direction, as, for example, "One is bigger than the

other" (for fly and butterfly). It is then permissible to ask: "_Which

is bigger?_"

SCORING. Passed if a real difference is given in _two out of three

comparisons_. It is not necessary, however, that an _essential_

difference be given; the difference may be trivial, only it must be a

real one. The following are samples of satisfactory and unsatisfactory


_Fly and butterfly_

_Satisfactory._ "Butterfly is larger." "Butterfly has bigger

wings." "Fly is black and a butterfly is not." "Butterfly is

yellow (or white, etc.) and fly is black." "Fly bites you and

butterfly don't." "Butterfly has powder on its wings, fly does

not." "Fly flies straighter." "Butterfly is outdoors and a fly

is in the house." "Flies are more dangerous to our health."

"Flies haven't anything to sip honey with." "Butterfly doesn't

live as long as a fly." "Butterfly comes from a caterpillar."

Sometimes a double contrast is meant, but not fully expressed;

as, "A fly is small and a butterfly is pretty." Here the thought

is probably correct, only the language is awkward.

Of 102 correct responses, 70 were in terms of size, or size plus

color or form; 12 were in terms of both form and color; 6 in

terms of color alone; and the rest scattered among such

responses as those mentioned above.

_Unsatisfactory._ These are mostly misstatements of facts; as:

"Fly is bigger." "Fly has legs and butterfly hasn't." "Butterfly

has no feet and fly has." "Butterfly makes butter." "Fly is a

fly and a butterfly is not." Failures due to misstatement of

fact are of endless variety. If an indefinite response is given,

like "The fly is different," or "They don't look alike," we ask,

"_How is it different?_" or, "_Why don't they look alike?_" It

is satisfactory if the child then gives a correct answer.

_Stone and egg_

_Satisfactory._ "Stone is harder." "Egg is softer." "Egg breaks

easier." "Egg breaks and stone doesn't." "Stone is heavier."

"Egg is white and stone is not." "Egg has a shell and stone does

not." "Eggs have a white and a yellow in them." "You put eggs in

a pudding." "An egg is rounder than a stone." We may also accept

statements which are only qualifiedly true; as, "You can break

an egg, but not a stone." Likewise double but incomplete

comparisons are satisfactory; as, "An egg you fry and a stone

you throw," "A stone is tough and an egg you eat," etc.

A little over three fourths of the comparisons made by children

of 6, 7, and 8 years are in terms of hardness. The other

responses are widely scattered.

_Unsatisfactory._ "A stone is bigger (or smaller) than an egg."

"A stone is square and an egg is round." "An egg is yellow and a

stone is white." "Stones are red (or black, etc.) and eggs are

white." "An egg is to eat and a stone is to plant." "An egg is

round and a stone is sometimes round."

It will be noted that the above responses are partly true and

partly false. The error they contain renders them unacceptable.

Most of the failures are due to misstatements as to size, shape,

or color, but occasionally one meets a bizarre answer.

_Wood and glass_

_Satisfactory._ "Glass breaks easier than wood." "Glass breaks

and wood does not." "Wood is stronger than glass." "Glass you

can see through and wood you can't." "Glass cuts you and wood

doesn't." "You get splinters from wood and you don't from

glass." "Glass melts and wood doesn't." "Wood burns and glass

doesn't." "Wood has bark and glass hasn't." "Wood grows and

glass doesn't." "Glass is heavier than wood." "Glass glistens in

the sun and wood does not."

An incomplete double comparison is also counted satisfactory;

as, "Wood you can burn and glass you can see through."

_Unsatisfactory._ "Wood is black and glass is white." (Color

differences are always unsatisfactory in this comparison unless

transparency is also mentioned.) "Glass is square and wood is

round." "Glass is bigger than wood" (or _vice versa_). "Wood is

oblong and glass is square." "Glass is thin and wood is thick."

"Wood is made out of trees and glass out of windows." "There is

no glass in wood."

The two most frequent types of failures are misstatements

regarding color and thickness. The other failures are widely


REMARKS. The test is one which all the critics agree in commending,

largely because it is so little influenced by ordinary school

experience. Its excellence lies mainly, however, in the fact that it

throws light upon the character of the child's higher thought processes,

for thinking means essentially the association of ideas on the basis of

differences or similarities. Nearly all thought processes, from the most

complex to the very simplest, involve to a greater or less degree one or

the other of these two types of association. They are involved in the

simple judgments made by children, in the appreciation of puns, in

mechanical inventions, in the creation of poetry, in the scientific

classification of natural phenomena, and in the origination of the

hypotheses of science or philosophy.

The ability to note differences precedes somewhat the ability to note

resemblances, though the contrary has sometimes been asserted by

logician-psychologists. The difficulty of the test is greatly increased

by the fact that the objects to be compared are not present to the

senses, which means that the free ideas must be called up for comparison

and contrast. Failure may result either from weakness in the power of

ideational representation of objects, or from the inadequacy of the

associations themselves, or from both. Probably both factors are usually


Intellectual development is especially evident in increased ability to

note _essential_ differences and likenesses, as contrasted with those

which are trivial, superficial, and accidental. To distinguish an egg

from a stone on the basis of one being organic, the other inorganic

matter requires far higher intelligence than to distinguish them on the

basis of shape, color, fragibility, etc. It is not till well toward the

adult stage that the ability to give very essential likenesses and

differences becomes prominent, and when we get a comparison of this type

from a child of 7 or 8 years it is a very favorable sign.

It would be well worth while to standardize a new test of this kind for

use in the upper years and especially adapted to display the ability to

give essential likenesses and differences. At year VII we must accept as

satisfactory any real difference.

One point remains. In the tests of giving differences and similarities,

it is well to make note of any tendency to _stereotypy_, by which is

meant the mechanical reappearance of the same idea, or element, in

successive responses. For example, the child begins by comparing fly and

butterfly on the basis of size; as, "A butterfly is bigger than a fly."

So far, this is quite satisfactory; but the child with a tendency to

stereotypy finds himself unable to get away from the dominating idea of

size and continues to make it the basis of the other comparisons: "A

stone is larger than an egg," "Wood is larger than glass," etc. In case

of stereotypy in all three responses, we should have to score the total

response failure even though the idea employed happened to fit all three

parts of the question. As a rule it is encountered only with very young

children or with older children who are mentally retarded. It is

therefore an unfavorable sign.

Although this test has been universally used in year VIII, all the

available statistics, with the exception of Bobertag's and Bloch's,

indicate that it is decidedly too easy for that year. Binet himself says

that nearly all 7-year-olds pass it. Goddard finds 97 per cent passing

at year VIII, and Dougherty 90 per cent at year VI. With the standard of

scoring given in the present revision, and with the substitution of

_stone and egg_ instead of the more difficult _paper and cloth_, the

test is unquestionably easy enough for year VII.