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5 The Mind-Made Firmament
made to exist in our world model. The same is true in other species: The objects
that have been individuated are then recognized by members of the species,
who learn how to act appropriately toward them.
To individuate a chunk of the world is to grant it recognition as an existing
thing. It is not only material objects that are individuated, but also categories
of objects, kinds of events, things people do, and so on. These become parts
of our version of reality, and are inserted into our world model. There are
countless different ways that reality can be divided up into parts, and the one
selected for us is our scheme of individuation, or scheme of segmentation.
Clearly it is not an individual creature that carves up the world: The organization into objects and categories is a product of evolution acting over great
spans of time and inherited by every organism. A scheme of segmentation is
pragmatic and purposeful: Every detail is there for a reason. A segmentation
is shaped by the external forces which impinge on organisms, in combination
with the manner in which an organism’s anatomy enables it to respond.
If a hypothetical organism had the power to see the world with perfect
accuracy and fidelity, what would such a creature see? Surely not the image
projected onto its retina, for that picture is a perpetually fluctuating pattern of
light, shade and colors. Instead, let’s ask: What are creatures meant to see? If
evolution did its job right, the animal would make out precisely the things in
the world that impact its survival. That is exactly what all creatures see—and
it’s the primary reason for having a segmentation of the world. Out of the
surrounding turmoil, the brain detaches the objects that are essential in an
animal’s activity.
A species’ scheme of segmentation is biologically based: It determines how
individuals perceive the world visually—how the scene which they behold
is composed of separate objects. Psychological experiments have shown that
the moment we lay eyes on a scene, we’re aware of the specific objects in
it. The psychologist Irving Biederman has found that we cannot turn off the
process leading spontaneously to object recognition. The British neuroscientist
Glynn Humphreys likewise showed that people cannot process the global shape
of objects without concurrently accessing their identity. We are biologically
constrained to perceive the segmentation of reality in just one way. 1
The way the mind carves up the world into separate entities is revealed also
in human speech. The objects that we perceive, and that claim existence in
the world we see, turn up as words in our language. We have words for solid
objects, other words for their features and qualities, and yet others for actions
and events. Human language brings out the fact that it is not only material
objects that are the constituents of the world as we know it: There are many
other kinds of constituents, for example things people do, actions they take,
5 The Mind-Made Firmament
made to exist in our world model. The same is true in other species: The objects
that have been individuated are then recognized by members of the species,
who learn how to act appropriately toward them.
To individuate a chunk of the world is to grant it recognition as an existing
thing. It is not only material objects that are individuated, but also categories
of objects, kinds of events, things people do, and so on. These become parts
of our version of reality, and are inserted into our world model. There are
countless different ways that reality can be divided up into parts, and the one
selected for us is our scheme of individuation, or scheme of segmentation.
Clearly it is not an individual creature that carves up the world: The organization into objects and categories is a product of evolution acting over great
spans of time and inherited by every organism. A scheme of segmentation is
pragmatic and purposeful: Every detail is there for a reason. A segmentation
is shaped by the external forces which impinge on organisms, in combination
with the manner in which an organism’s anatomy enables it to respond.
If a hypothetical organism had the power to see the world with perfect
accuracy and fidelity, what would such a creature see? Surely not the image
projected onto its retina, for that picture is a perpetually fluctuating pattern of
light, shade and colors. Instead, let’s ask: What are creatures meant to see? If
evolution did its job right, the animal would make out precisely the things in
the world that impact its survival. That is exactly what all creatures see—and
it’s the primary reason for having a segmentation of the world. Out of the
surrounding turmoil, the brain detaches the objects that are essential in an
animal’s activity.
A species’ scheme of segmentation is biologically based: It determines how
individuals perceive the world visually—how the scene which they behold
is composed of separate objects. Psychological experiments have shown that
the moment we lay eyes on a scene, we’re aware of the specific objects in
it. The psychologist Irving Biederman has found that we cannot turn off the
process leading spontaneously to object recognition. The British neuroscientist
Glynn Humphreys likewise showed that people cannot process the global shape
of objects without concurrently accessing their identity. We are biologically
constrained to perceive the segmentation of reality in just one way. 1
The way the mind carves up the world into separate entities is revealed also
in human speech. The objects that we perceive, and that claim existence in
the world we see, turn up as words in our language. We have words for solid
objects, other words for their features and qualities, and yet others for actions
and events. Human language brings out the fact that it is not only material
objects that are the constituents of the world as we know it: There are many
other kinds of constituents, for example things people do, actions they take,