is  also    illustrated in  the common  statement   that    what    one gets    from    an  art exhibit
or  a   concert depends on  what    he  brings  to  it. He  who brings  no  knowledge,  no
memory,  no  images  from    other   pictures    or  music   will    secure  but     relatively
barren  percepts,   consisting  of  little  besides the mere    sensory elements.   Truly,  "to
him that    hath    shall   be  given"  in  the realm   of  perception.
The  Accuracy    of  Percepts    Depends     on  Experience.—We  must    perceive
objects through our motor   response    to  them    as  well    as  in  terms   of  sensations.
The boy who has his knowledge   of  a   tennis  racket  from    looking at  one in  a   store
window, or  indeed  from    handling    one and looking it  over    in  his room,   can never
know    a   tennis  racket  as  does    the boy who plays   with    it  on  the court.  Objects get
their   significance    not alone   from    their   qualities,  but even    more    from    their   use as
related to  our own activities.
Like    the child,  we  must    get our knowledge   of  objects,    if  we  are to  get it  well,
from     the     objects     themselves  at  first   hand,   and     not     second  hand    through
descriptions    of  them    by  others. The fact    that    there   is  so  much    of  the material
world   about   us  that    we  can never   hope    to  learn   it  all,    has made    it  necessary   to  put
down     in  books   many    of  the     things  which   have    been    discovered  concerning
nature. This    necessity   has,    I   fear,   led many    away    from    nature  itself  to  books—
away    from    the living  reality of  things  to  the dead    embalming   cases   of  words,  in
whose   empty   forms   we  see so  little  of  the significance    which   resides in  the
things   themselves.     We  are     in  danger  of  being   satisfied   with    the    forms    of
knowledge   without its substance—with  definitions contained   in  words   instead of
in  qualities   and uses.
Not Definitions,    But First-hand  Contact.—In like    manner  we  come    to  know
distance,   form    and size.   If  we  have    never   become  acquainted  with    a   mile    by
actually    walking a   mile,   running a   mile,   riding  a   bicycle a   mile,   driving a   horse   a
mile,   or  traveling   a   mile    on  a   train,  we  might   listen  for a   long    time    to  someone
tell    how far a   mile    is, or  state   the distance    from    Chicago to  Denver, without
knowing  much    about   it  in  any     way     except  word    definitions.    In  order   to
understand   a   mile,   we  must    come    to  know    it  in  as  many    ways    as  possible
through sense   activities  of  our own.    Although    many    children    have    learned that    it
is  25,000  miles   around  the earth,  probably    no  one who has not encircled   the
globe   has any reasonably  accurate    notion  just    how far this    is. For words   cannot
take    the place   of  perceptions in  giving  us  knowledge.  In  the case    of  shorter
distances,  the same    rule    holds.  The eye must    be  assisted    by  experience  of  the
muscles  and     tendons     and     joints  in  actually    covering    distance,   and     learn   to
associate   these   sensations  with    those   of  the eye before  the eye alone   can be  able
