140 Animal Intelligence 
easily be determined in any case. The only case of total 
loss of the association (No. 1 in C) is so exceptional that I 
fancy something other than lapse of time was its cause. 
The main interest of these data, considered as quantitative 
estimates, is not psychological, a show 
what a tremendous advantage thewell-devéleped associa- 
tion-process is to an animal. iThe ways to different feeding 
grounds, the actions of enémies, the appearance of noxious 
foods, are all connected permanently with the proper re- 
action by a few experiences which need be reénforced only 
very rare Of course, associations without any perma- 
nence cont be useless, but the usefulness increases im- 
mensely with such a degree of permanence as these results 
witness. An interesting experiment from the biological 
point of view would be to see how infrequently an experience 
could occur and yet lead eventually to a perfect association. 
An experiment approximating this is recorded in the time- 
curves for Box H in Figure 7, on page 47. Three trials at a 
time were given, the trials being two or three days apart. 
As may be seen from the curves, the association was readily 
formed. 
The chief psychological interest of these data is ac they 
show that permanence o sociations-is-nal. memory. The 
fact that a‘Cat; when after an interval she is put into bex G, 
proceeds to immediately press the thumb piece and push 
the door, does not at all mean that the cat feels the box 
to be the same from which she weeks ago freed herself by 
pushing down that thumb piece, or thinks about ever 
having felt or done anything in that box. She does not 
refer the present situation to a situation of the past and real- 
ize that it is the same, but simply feels on being confronted. 
with that situation the same impulse which she felt before. 
She does the thing now for just the same reason that she 
