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What Abilities Could Usefully be Innate?
Taking into account what the world is like and what our nervous
systems are like, what knowledge and abilities are possibly and
usefully innate? Many of them correspond to the facts about the
world discussed in section 2.
- some objects persist even while not sensed
- Having this
prejudice is fundamental to the survival of humans--and probably to
other land vertebrates. A dog chasing a ball will look for it if it
disappears behind something.
- identify object
- Identify a part of the current stimulus pattern
as coming from an object. Remember aspects of the object as the
same as a previous object or as coming from a new object. The task
is basically the same whether the stimuli are visual, tactile,
auditory or olfactory or a combination. Success involves
recognizing repeated instances of the same object or the same kind
of object. Present machine learning schemes are more suited to
recognizing kinds of objects than for recognizing individual
objects. Both are needed.
What innate structures are suited for this? At least some of these
structures are independent of the sensory modality.
- natural kinds
- The child is predisposed to name kinds of
entities and to expect that the objects of a kind that is recognized
by superficial properties will have additional properties in common.
For example, adults call some objects lemons, and all lemons turn
out to have similar taste and to have similar seeds.
- three-dimensional objects
- The world contains three-dimensional
objects, and humans know about them. While non-blind people usually
get most of their information about objects from seeing them, what
we know about objects should not be regarded as a collection of 2-d
pictures. The objects are far more stable than pictures of them can
be, because they are seen at a variety of angles and lighting
conditions. We learn about objects from 2-d pictures, but they are
not constructs from 2-d pictures.
Advocates of an initial tabula rasa have proposed that a baby
learns that its sensations should be organized around external
objects. Maybe a mechanism for learning this could exist, but a
baby would learn faster if this much were innate. In fact
animal thought also seems to presume external objects. Many
specific instincts, e.g. related to hunting, presuppose them.
A baby also has no difficulty with two dimensional representations
of three dimensional objects. A baby apparently doesn't have to
be taught that a picture of a dog in a book represents some real dog.
- objects have colors
- Our visual system goes to a lot of trouble
to ascribe colors to objects in ways that are independent of
lighting. When this fails, we notice it.
- expect an object to have a location
- Since a physical object a
person has perceived ordinarily continues to have a location even
when it is no longer perceived, because it or the person has moved,
it is advantageous for the person to expect it to have a location.
He might want to look for it or reason about its effects on other
objects, e.g. as described in [Spe94].
- perceive motion as continuous
- Although our visual perceptions
of objects are discrete because of our saccadic movements, we
perceive objects as moving continuously. We evolved to interpret
our sense data, and not just visual sense data, in terms of
continuous motion. Perceiving motion as continuous may have evolved
very early among vertebrates. I suppose this involves an
approximate differentiation of the position.
- recognize parts
- Recognize parts of an object and their relations
to the others. It would be interesting if there were an ability
to recognize certain physical structures, e.g. towers and walls,
analogous to the ability to recognize a grammatical sentence.
- kind of situation
- Identify the current situation as being of a
certain kind.
- focussed curiosity
- In the Shannon quantitative measure of
information, there is just as much information to be obtained from
the pattern of saw marks on the boards of my office wall as there is
about what is available for lunch or what can be obtained by
research on artificial intelligence. Curiosity needs to be focussed
on what is potentially relevant to the baby or robot. Notice that
human curiosity, as it ought to be, is quite broad--but it is also
selective. Part of the answer is that curiosity is focussed on
getting more information about kinds of object that have been
identified.
- noise rejection
- Certain appearances are usually noise,
e.g. shadows. The child may be predisposed to regard shadows as
noise, i.e. to regard an object as continuing through a shadow and
to ignore the edges of shadows. Elizabeth Spelke [Spe94]
considers the recognition of shadows to be non-innate.
- grammar of goal regression
- The recognition that a goal is
achievable because it is either already achieved or all the
preconditions of an action that achieves it are achievable. This
can be regarded as the grammar of a specific language GR, but unlike
the grammar of a spoken languages, the grammar of GR is
universal.10
- principle of mediocrity
- The baby is like other people. It can
learn about its own capabilities from observing others, and it can
learn about others by putting itself in their places. 11
- introspection
- Recent work in psychology, [FO99] and
[JHFF00], shows
that children develop some introspective ability by age 3, and this
ability improves with age. [McC96] discusses the introspective
abilities required by a robot.
- pointer effect
- When one uses a pointer, e.g. a pencil, to
explore or manipulate in a container, one's senses refer to the
end of the pointer and not to one's hands. This seems to be innate,
but is not a feature of helpless young babies. Maybe there's a
standard name for what I've called ``pointer effect''.
It would be interesting if there were innate non-linguistic human
mental abilities that are not present in animals. Nothing appears
obvious, but maybe the innate part of human number sense is
qualitatively different from that of animals.
Some abilities require early experience to acquire. For example,
people blind from birth who gain sight as adults don't acquire an
image processing system fully adapted to the world as it is. However,
there is no reason to expect that they could acquire an image
processing system adapted to a quite different visual world. If this
is so, then the image processing system is still basically innate.
Next: Features of a Language
Up: THE WELL-DESIGNED CHILD
Previous: Human Mental Characteristics
Contents
John McCarthy
2008-09-18