These are excerpts and elaborations from my book "The Nature of Consciousness"
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Memories are Made of This The mind’s cognitive
faculties depend to a great extent on memory. If we could not learn and
remember at all, our cognitive life would be virtually non-existent. If we could not remember
where we live, where our office is, how to lace our shoes, how to drive a car,
how to speak, and so forth, we would be mere objects devoid of real life. In
fact, we would probably last only a few minutes. The more complex the organism,
the more essential memory is to its
survival because so much is required to keep the organism alive. Even the worst cases of
amnesia do not completely erase memory. A patient who suffers complete amnesia
does not remember anything from some date on in the past, but still remembers a
lot of vital facts about living in the world. Evolutionarily speaking,
memory provided a considerable advantage to creatures capable of remembering
where water was or where predators lived. The more refined one's memory, the
easier to navigate the environment, to survive in it and to find food in it. That animal memory is not
just like a computer memory is a fact due precisely to the tasks that were
required by it, tasks that rarely require perfection but do require speed and
capacity. Learning to bike and memorizing the emergency phone number are both
important tasks, but they are usually achieved in rather different ways. Thus
it is not even correct to speak of "memory" as if it were just one
task. It is probably more appropriate to speak of "memories". Memory is more than storage.
Memory is also recognition. We are capable of recognizing a tree as a tree even
if we have never seen that specific tree before. No two trees are alike. And
even a specific tree never appears the same to us, as the perspective, the
wind, the lighting can all dramatically change its appearance. In order to
recognize a tree as a tree, and as a specific tree, we use our
"memory". Whenever we see something, we ransack our memory looking
for "similar" information. Without memory we would not see trees, but
only patches of brown and green. The process of thinking
depends on the process of categorizing: the mind deals with concepts, and
concepts exist because memory is capable of organizing experience into
concepts. Our mind, ultimately, looks like a processor of concepts. The mind's
functioning is driven by memory, which is capable of organizing knowledge into
concepts. So much so that, inevitably, a theory of memory becomes a theory of
concepts, and a theory of concepts becomes a theory of thought. Cognition revolves around
memory. All cognitive faculties use memory and would not be possible without
memory. They are, in fact, but side effects of the process of remembering.
There is a fundamental unity of cognition, organized around the ability to
categorize, to create concepts out of experience. Memory's task is easily
summarized: to remember past experience. But, unlike the memory of a computer,
which can remember exactly its past experience, human memory never remembers exactly.
The most peculiar feature of
our memory is, perhaps, the fact that it is so bad at remembering. Our memory
does not only forget most of the things that happen, but, even when it
remembers, it does a lousy job of remembering. Memory of something is almost
always approximate. Many details are forgotten right away. If we want to
remember a poem by heart, we have to repeat it to ourselves countless times.
And sometimes memory is also very slow: sometimes it takes a long time to
retrieve a detail of a scene, sometimes it will take days before the name of a
person comes back to mind. Rather than
accessing memories by calendar day or person's name, we seem to access them by
associations, which is a much more complicated way to navigate in the
past. It is hard to think of
something without thinking also of something else. It is hard to focus on a
concept and not think of related concepts. And the related concepts that come
to mind when we focus on a concept are usually things we care about, not
abstract ideas. If we focus on "tree", we may also remember a
particular hike in the mountains or an event that occurred by a tree. We build
categories, we relate categories among them, we associate specific episodes
with categories. For an entity that is
supposed to be just a storage device, anomalies abound. For example, we cannot
count very easily. Do you know how your
home looks like? Of course. How many windows does it have? You have looked at
your home thousands of times, but you cannot say for sure how many windows it
has. If you see a flock of birds in the
sky, you can tell the shape, the direction, the approximate speed... but not
how many birds are in the flock, even if there are only six or seven. Another
weird feature of our memory is that it is not very good at remembering the
temporal order of events: we have trouble remembering if something occurred
before or after something else. On the other hand, our memory is good at
ordering objects in space and at counting events in time. Human memory is a bizarre
device that differs in a fundamental way from the memory of machines: a camera
or a computer can replicate a scene in every minute detail, whereas our memory
was just not designed to do that. What was our memory designed
to do? Back to the beginning of the chapter "Memory" | Back to the index of all chapters |
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