psych2 |
An
Example of a "Learning Process" Journal (using the 2 colored
box format) |
|
November
5, 2003 |
Book: The Number Sense by Stanislas Debaene
Source: Oxford University Press 1997
|
I have read the first chapter and want to
begin making notes. This time I want to make my notes for each
chapter as soon as I have completed reading/highlighting the
chapter. |
Yellow highlighted passages: Introduction
- "Every single thought we entertain, every calculation we
perform, results from the activation of specialized neuronal
circuits implanted in our cerebral cortex." [p. 4]
- "Even our digital notation of numbers ... is the fruit
of a slow process of invention over thousands of years."
[p. 4]
- "The slow cultural evolution of mathematical objects is
a product of a very special biological organ, the brain,
that itself represents the outcome of an even slower biological
evolution governed by the principles of natural selection."
[p. 4]
- "All people possess, even within their first year of life,
a well-developed intuition about numbers." [p. 5]
- "Humans, however, have been endowed by evolution with a
supplementary competence: the ability to create complex symbol
systems, including spoken and written language. Words, or
symbols, because they can separate concepts with arbitrarily
close meanings, allow us to move beyond the limits of approximation."
[p. 5]
- "The concept of number, hinted at by the Babylonians, refined
by the greeks, purified by the Indians and the Arabs, axiomitized
by Dedekind and Peano, generalized by Galois, has never ceased
to evolve from culture to culture - obviously, without requiring
any modification of the mathematican' genetic material! [p.
6]
- "Our brain ... has been endowed since time immemorial with
an intuitive representation of quantities. ... Our memory
... is not digital but works by association of ideas. This
is probably the reason why we have such a hard time remembering
the ... multiplication table." [p. 7]
- "Mathematicians have worked hard for centuries to improve
the usefulness of numerical notations by increasing their
genrality, their fields of application, and theri formal
simplicity." [p. 7]
|
The first quote should never be forgot!
We should be both amazed and humbled by the history of mathematics.
Why did it take so long for us to arrive at our present notational
conventions? But look how impressive our accomplishments in
mathematics have been!
Humans are fundamentally analog machines, but our use of symbols
permits us to also be digital. We are bilingual! |
Yellow highlighted passages: Chap. 1 Talented
and Gifted Animals
- "In nuerous species, estimating the number and ferocity of
predatores, quatifying and comparing the return of two sources
of food, are matters of life and death." [p. 14]
- "The ability to compare two numerical quantities ... is widespread
among animals." [p. 25]
- "... the nature of these errors provides important cues about
the nature of the mental representation employed. ... they
demonstrate ... that animals do not possess a digital or discrete
representation of numbers." [p. 27]
- "To a rat, numbers are just approximate magnitudes." [p.
30]
- "When we count, we use a precise sequence of number words.
... Not so for rats. ... The difference with our verbal counting
is so enormous that we should perhaps not talk about 'number'
in animals at all ...'numerosity' ... enables animals to estimate
how numerous some events are, but does not allow them to compute
their exact number." [p. 34 - 35]
- "While we may marvel at animals' ability to manipulate approximate
representations of numerical quantities, teaching them a symbolic
language seems to go against their natural proclivities." [p.
39]
- "... if our closest cousins, the chimpanzees possess some
competence for arithmetic, and if species as different as rats,
pigeons, and dolphins are not devoid of numerical abilities,
it is likely that we Homo sapiens have received a similar heritage.
Our brains, like the rat's, are likely to come equipped with
an accumulator that enables us to perceive, memorize, and compare
numerical magnitudes." [p. 40]
- Many outstanding differences separate human cognitive abilities
from those of other animals:
- we have an uncanny ability to develop symbol systems
...
- we are also endowed with a cerebral language organ that
enables us to express our thoughts and to share them with
other members of our species ...
- our ability to devise intricate plans for actions, based
on a retrospective memory of past events and a prospective
memory of future possibilities, seems to be unique in the
animal kingdom." [p. 40]
|
The basic point is that we are more than
simply analog numerical processors, using language and symbol
systems to develop new ideas.
|
Yellow highlighted passages: Chap. 2 Babies
Who Count
- "Yet if our working hypothesis is correct, the human brain
is endowed with an innate mechanism for apprehending numerical
quantities, one that is inherited from our evolutionary past
and that guides the acquisition of mathematics. To influence
the learning of number words, this protonumerical module must
be in place before the period of exuberant language growth
that some psychologists call the 'lexical explosion', which
occurs around a year and half of age." [p. 41]
- "...replacing marbles with palatable treats (M&Ms) ... the
children were allowed to pick up one of the two rows and consume
it right away. ... a majority of children selected the larger
of the two numbers, even when the length of the rows conflicted
with number." [p. 45]
- "That three- and four-year-old children select the more numerous
row of candy ... conflicts directly with Piaget's theory. But
there is more. ... the youngest children, who were about two
years old, succeeded perfectly in the test, both with marbles
and with M&Ms. Only the older children failed to conserve the
number of marbles. ... For some reason, these tests seem to
confuse the older children." [p. 45]
- "I believe that what happens is this: Three- and four-year
olds interpret the experimenter's quesions quite differently
from adults. The wording of the questions and the context in
which they are posed mislead children into believing that
they are asked to judge the length of the rows rather than
their numerosity. Remember that, in Piaget's seminal experiment,
the experimenter asks the very same question twice; 'Is it
the same thing, or does one row have more marbles?' He first
raises this question when two rows are in perfect one-to-one
correspondence, and then again after their length has been
modified. What might children think of these two successive
questions? Let us suppose that the numerical equality of the
two rows is obvious to them. They must find it quite strange
that a grown-up would repeat the same trivial question twice.
Indeed, it constitutes a violation of ordinary rules of conversation
to ask a question whose answer is already known by both speakers.
... 'If these grown-ups ask me the same question twice, it
must be because they are expecting a different answer. ..."
[p.45-46]
- "Piagetian conservation tasks ... this is an active domain
of research that still attracts many researchers throughout
the world." [p. 47]
- "... we now know what Piagetian tests are not about. ...
these are not good tests of when a child begins to understand
the concept of number." [p. 47]
- "The experiments that I have described so far challenge the
Piagetian time scale for numerical development by suggesting
that children 'conserve number' at a much earlier age than
was once thought possible." [p. 47-48]
- "... even newborns coud discriminate numbers 2 and 3 a few
days after birth." [p. 50]
- "... use a sucking rhythm rather than a gaze orientation
..." [p. 51]
- "While young children's numerical abilities are real, they
are strictly limited to the most elementary of arithmetic."
[p. 56]
- "... only occassionally are they shown to differentiate three
versus four. And never can a group of babies under one year
of age distinquish four dots from five or even from six." [p.
57]
- "Babies, however, ... most likely possess only an approximate
and continuous mental representation of numbers." [p. 57]
- "Newborns readily distinquish two objects from three ...
their brain apparently comes equipped with numerical detectors
that are probably laid down before birth." [p. 61]
- "Younger babies seem unaware of the natural ordering of numbers."
[p. 63]
|
I was not aware of the use of a sucking action
as a substitute for watching their eyes.
I also was not aware that 2 year-olds could "conserve number"
but that three-year-olds had difficulty.
I agree with the conclusion about pre-wiring, that it only
refers to very small numbers, and that it does not imply any abstract
sense of number or the relationship among numbers. It is simply
a primitive sense of which is different. |
Reminder: each "Learning" session has a new web page.
|