PLAY 251 
to-day as a fighting-play or a hunting-play. It is open to 
question, however, whether either the instinctive behaviour or 
the conscious situation in the one case and the other is so 
nearly identical that the playful fight or hunt can fairly 
be called the same instinctive procedure as the serious 
combat or chase. We may hold, with Professor Groos, that 
the one is an invaluable preparation for the other without 
identifying them as the same behaviour under different con- 
ditions. Indeed the conditions are so different that the identi- 
fication seems strained. The question may be left open, 
however, without impairing the value of Professor Groos’s 
suggestion. And we may divide the preparatory behaviour in 
what is commonly called play under two heads: first, general 
preparation for varied modes of serious effort in after-life ; and 
secondly, special preparation for particular forms of this after- 
effort. Under the first will fall what Professor Groos terms 
experimentation and movement play, including what Dr. Stout, 
who fully realizes its importance, calls “manipulation ” ; * 
under the second, such forms as hunting-play and fighting- 
play. 
Nothing is more characteristic of the young of intelligent 
animals than the variety and persistency of their behaviour, 
their sensitiveness to stimuli of many different kinds, their 
restlessness of swiftly changing attention and response, with 
occasional pauses of continued effort in some special direction. 
Constantly on the alert, they exhibit in all its shifting phases 
behaviour which we interpret as indicating curiosity, inquisitive- 
ness, love of mischief, destructiveness, and so forth. The facts 
are so familiar to every observer of young animals that it is 
unnecessary to give any detailed illustration. Watch a kitten 
in this stage of its development and carefully note its behaviour 
during half an hour; the variety of effort, the réles played 
by trial, failure, and success, the gain of skill and control over 
behaviour, will at once be evident. Or devote an equal space 
of time to observing young jays, magpies, or jackdaws. Every 
projecting piece of wire or bit of wood in their cage is pulled 
* “ Manual of Psychology,” p. 327. 
