Page 196 - Deep Learning

The Growth of Competence 179

chessmen four feet high. These are moved by walking onto the chessboard, lift-
ing them up and waddling them over to their destination squares, very different
physical movements from those used to make the same move on a traditional
board or on a chess-playing computer. The physical movements involved in
moving a piece can vary along any number of dimensions such as speed, degree
of extension, the angles of the shoulder and elbow joints, the number of fingers
extended, the stiffness of the fingers, and so on, and these quantitative varia-
15
tions are of great interest to those who study motor coordination. But as long
as the chess piece ends up in the same square, it is nevertheless the same action,
from the point of view of chess, as the movement of a chess piece by hand on a
tabletop board. The intuitive distinction between tasks that are cognitive (alge-
bra, chess, programming, writing, etc.) and tasks that are physical (baseball,
dancing, hammering, pottery, etc.) can be defined in terms of whether the suc-
cess of an action depends on the physical properties (amplitude, force, speed,
etc.) of the associated movements or is independent of those aspects.

Goals

Action is purposeful. Water might be poured in the service of making tea,
and a button is typically pushed to make some machine do what is desired
of it. A goal is a mental representation of a future state of affairs, be it that i
have a cup of tea in my hand or that the elevator arrives. Although goals are
like descriptions, they are neither true nor false. if a goal were true, it would
be accomplished already. to say that a goal is false is technically accurate but
peculiar. Unlike a false belief, a goal description is intentionally formulated to
differ from the current state of affairs; no use wishing for things you already
have. Goals are neither true nor false but desired.
Goals and actions need to be distinguished because people can pursue one
and the same goal through different actions. if the kitchen in your new home has
an unfamiliar layout, the actions needed to make a cup of tea might change – the
tea is now in a cupboard to the left instead of to the right, forcing you to make
a change in motor behavior – but the goal, the cup of tea, remains the same.
Unless goals are represented separately from the relevant actions, goals cannot
remain constant while actions vary. Flexible behavior requires that we can pur-
sue a goal through different actions depending on the circumstances, and this in
turn requires distinct mental representations for goals and actions. 16
Goals vary with respect to the amount of time they control a person’s
behavior. to make a cup of tea takes a few minutes, but to fill the cup of life
takes longer. Andrew Corrigan-Halpern and i refer to the duration of the