Part 8

In a second control series given on the following day, June 12, confusion appeared, but less markedly. For the first setting, a correct choice was made with deliberation. For the second setting, box 3 was immediately chosen, as should have been the case in the regular series of settings. Sobke seemed confused when he emerged from this box and had difficulty in locating the right one. Then followed direct correct choices for settings 3, 4, and 5. For setting 6, there is recorded a deliberately made wrong choice, and so on throughout the series, the choices being characterized by deliberateness and definite search for the right box. Uncertainty was plainly indicated, and in this the behavior of the animal differed markedly from that in the concluding series of the regular experiment.

It seems safe to conclude from the results of these control series that Sobke has no free idea of the relation of secondness from the right and is chiefly dependent upon memory of the particular settings for cues which lead to correct choice.

Problem 3. Alternately First at Left and First at Right

For four successive days after the last control series in connection with problem 2, Sobke was merely fed in the apparatus according to previous description (p. 43). He exhibited a wonderfully keen appetite and was well fed during this interval between problems.

The method of experimentation chosen for problem 3 in the light of previous experience was that of confining the monkey for a short time, ten to fifteen seconds, in the wrong box, in each of the first ten mistakes for a given trial, and of then aiding him to find the right box by the slight and momentary raising of the exit door. Aid proved necessary in a few of the trials during the first four days. Then he worked independently. As work progressed it was found possible and also desirable to increase the period of confinement, and in the end, sixty seconds proved satisfactory. It was also thought desirable to increase the number of trials per day from a single series during the early days to two or even three series from June 29 on. Often three series could be given in succession without difficulty. During the early trials on this problem Sobke worked remarkably well, but later his willingness diminished, evidently because of his failure readily to solve the problem, and it became extremely difficult to coax him into the apparatus. On days when he entered only reluctantly and as it seemed against his will, he was likely to be nervous, erratic, and often slow in making his choices, but above all he tended to waste time by not returning to the starting point, preferring rather to loiter in the alleyways or run back and forth.

TABLE 6

Results for Sobke, P. rhesus, in Problem 3

========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+======== | No. | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | | | | | Ratio Date | of | | | | | | | | | 3.4.5.6 | 3.4.5.6 | R | W | R | W | of | trials | 5.6.7 | 5.6.7 | 1.2.3.4.5.6 | 1.2.3.4.5.6 | 4.5.6.7.8 | 4.5.6.7.8 | 2.3.4.5 | 2.3.4.5 | 7.8.9 | 7.8.9 | | | | | R to W --------+-----------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+---+---+---+---+-------- | | | | | | | | | | | | | | | | June | | | | | {3.1.2.1 | {7.8.7.8 | | | | {9.8.7.9 | | | | | | 17 | 1--10 | {6.6.7.6 | 5.7 | {4.4.3.5.4 | {4.4.2.1 | {8.8.7.8 | 8 | 2 | 3.2.5 | {8.7.6.9 | 3.8.9 | 2 | 8 | 2 | 8 | 1:4.00 | | {6.5 | | {5.4.2.1 | {5.4.6* | {7.7.4* | | | | {8.7.3* | | | | | | | | | | | | | | | | | | | | | | | | | | {3.4.2.5 | | {8.7.7.5 | | | | | | | | | | 18 | 11--20 | 6.6.6.5 | 5.7 | {4.5.6.4 | 3.1.4.3.6 | {8.8.7.8 | 8 | 3.2 | (3.4.2.4 | 9.8.8.7.3 | 8.6.9 | 1 | 9 | 1 | 9 | 1:9.00 | | | | {2.3.1* | | {7.8.4* | | | {4.5 | | | | | | | | | | | | | | | | | | | | | | | | | | | {3.6.5.4 | | {8.8.7.7 | | | | | | | | | | 19 | 21--30 | 6.5 | 7 | {2.5.2.6 | 3.6 | {7.8.8.8 | 8 | 4.3.2 | {3.2.4.2 | {9.8.7.9.7 | 9 | 3 | 7 | 3 | 7 | 1:2.33 | | | | {3.5.1* | | {8.4 | | | {2.5 | {6.5.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | (8.8.8.8 | | | | {9.9.8.9 | | | | | | 21 | 31--40 | 6.5 | 5.6.5.7 | {3.5.4.6 | 2.5.3.6 | {7.8.3.8 | 8 | 4.2 | 2.5 | {9.5.9.9 | 9 | 2 | 8 | 2 | 8 | 1:4.00 | | | | {4.3.5.1 | | {8.7.4* | | | | {9.9.3* | | | | | | | | | | | | | | | | | | | | | | 22 | 41--50 | 7.6.5 | 6.5.5.7 | 1 | 2.1.3.6 | {8.8.8.8 | 8 | 2 | 2.3.2.2.5 | {9.8.9.8.7 | 9 | 4 | 6 | 4 | 6 | 1:1.50 | | | | | | {7.8.4 | | | | {6.5.9.3 | | | | | | | | | | | | | | | | | | | | | | 23 | 51--60 | 5 | 6.5.7 | 1 | {1.2.1.1 | 8.5.4 | 8 | 5.4.2 | 2.4.2.5 | {9.8.4.9 | 9 | 4 | 6 | 4 | 6 | 1:1.50 | | | | | {3.2.6 | | | | | {7.3 | | | | | | | | | | | | | | | | | | | | | | 24 | 61--70 | 7.6.5 | 7 | 2.3.1 | 2.1.5.4.2.6 | 8.7.8.4 | 8 | 4.5.4.3.2 | 2.2.4.5 | 9.7.6.8.3 | 9 | 3 | 7 | 3 | 7 | 1:2.33 25 | 71--80 | 6.5 | 5.7 | 3.1 | 6 | 8.5.4 | 8 | 2 | 3.2.5 | 9.8.7.3 | 3.9 | 3 | 7 | 3 | 7 | 1:2.33 | | | | | | | | | | | | | | | | 26 | 81--90 | 7.7.6.5 | 6.5.7 | 3.1 | {1.4.1.1 | 8.4 | 8 | 5.4.2 | 2.5 | 9.8.9.6.3 | 9 | 2 | 8 | 2 | 8 | 1:4.00 | | | | | {5.1.6 | | | | | | | | | | | | | | | | | | | | | | | | | | | 28 | 91--100 | 7.6.5 | 7 | 1 | 1.2.4.6 | 8.4 | 8 | 2 | 3.2.2.2.5 | 9.8.8.7.9.3 | 9 | 5 | 5 | 5 | 5 | 1:1.00 | | | | | | | | | | | | | | | | 29 | 101--110 | 7.6.5 | 5.7 | 1 | {1.1.5.3 | 8.4 | 8 | 2 | 4.2.5 | {9.9.8.9.4 | 9 | 4 | 6 | | | | | | | | {2.1.6 | | | | | {9.7.6.3 | | | | | | | | | | | | | | | | | | | | | | " | 111--120 | 6.5 | 6.5.7 | 1 | 2.1.1.3.6 | 8.5.4 | 8 | 2 | 3.2.5 | 9.8.7.6.4.3 | 9 | 4 | 6 | 8 |12 | 1:1.50 30 | 121--130 | 5 | 6.5.6.5.5.7 | 1 | 3.1.6 | 8.7.6.8.5.4 | 8 | 2 | 4.2.4.2.5 | 9.3 | 9 | 5 | 5 | | | " | 131--140 | 5 | 7 | 1 | 2.3.6 | 8.5.6.4 | 8 | 2 | 5 | 9.8.3 | 3.9 | 6 | 4 |11 | 9 | 1:0.82 July | | | | | | | | | | | | | | | | 1 | 141--150 | 5 | 7 | 1 | 1.6 | 8.7.4 | 8 | 2 | 3.2.5 | 9.8.6.9.3 | 9 | 6 | 4 | | | " | 151--160 | 5 | 7 | 1 | 2.5.3.6 | 8.4 | 8 | 2 | 2.5 | 9.3 | 8.8.7.5.4.9 | 5 | 5 |11 | 9 | 1:0.82 2 | 161--170 | 6.5 | 7 | 1 | 2.6 | 8.4 | 8 | 2 | 3.5 | 9.3 | 9 | 5 | 5 | 5 | 5 | 1:1.00 3 | 171--180 | 6.5 | 7 | 1 | 1.5.6 | 8.4 | 8 | 2 | 3.5 | 9.3 | 9 | 5 | 5 | | | " | 181--190 | 5 | 7 | 1 | 4.6 | 8.6.4 | 8 | 2 | 5 | 9.8.4.8.5.3 | 9 | 7 | 3 |12 | 8 | 1:0.67 5 | 191--200 | 6.5 | 5.7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 9.5.3 | 9 | 6 | 4 | | | " | 201--210 | 5 | 7 | 6.1 | 2.6 | 8.6.4 | 8 | 5.3.5.4.3.2 | 4.3.5 | 9.7.3 | 9 | 4 | 6 |10 |10 | 1:1.00 | | | | | | | | | | | | | | | | 6 | 211--220 | 5 | 5.7 | 1 | 2.6 | 8.6.4 | 8 | 2 | 4.3.5 | 9.3 | {5.4.8.3 | 4 | 6 | | | | | | | | | | | | | | {8.5.4.9 | | | | | | | | | | | | | | | | | | | | | " | 221--230 | 5 | 7 | 1 | 5.3.6 | 8.6.8.4 | 8 | 4.2 | 3.2.5 | 9.3 | 9 | 5 | 5 | 9 |11 | 1:1.22 7 | 231--240 | 5 | 7 | 1 | 2.6 | 8.4 | 7.4.8 | 2 | 4.3.5 | 8.3 | 9 | 5 | 5 | | | " | 241--250 | 5 | 7 | 2.6.3.5.1 | 6 | 8.4 | 8 | 2 | 5 | 9.3 | 9 | 7 | 3 | | | | | | | | | | | | | | | | | | | | | | | {2.6.2.6.4 | | | | | | | | | | | | " | 251--260 | 5 | 7 | {6.3.2.6 | 6 | 8.4 | 8 | 2 | 5 | 9.5.3 | 9 | 7 | 3 |19 |11 | 1:0.58 | | | | {5.4.3.1 | | | | | | | | | | | | | | | | | | | | | | | | | | | | 8 | 261--270 | 7.5 | 7 | 1 | 6 | 8.4 | 8 | 5.2 | 5 | 8.3 | 8.5.4.9 | 5 | 5 | | | " | 271--280 | 5 | 7 | 2.6.4.6.1 | 6 | 8.5.8.4 | 7.4.8 | 5.5.3.5.2 | 5 | 9.3 | 9 | 5 | 5 |10 |10 | 1:1.00 | | | | | | | | | | | | | | | | 9 | 281--290 | 5 | 5.7 | 1 | 6 | 8.4 | 8 | 2 | 2.5 | 8.3 | {7.3.8.6.8 | 5 | 5 | | | | | | | | | | | | | | {4.7.3.9 | | | | | | | | | | | | | | | | | | | | | " | 291--300 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 9.3 | 9 | 8 | 2 | | | " | 301--310 | 5 | 7 | 1 | 6 | 8.4 | 8 | 5.2 | 5 | 9.5.3 | 9 | 7 | 3 |20 |10 | 1:0.50 10 | 311--320 | 5 | 7 | 1 | 6 | 8.4 | 7.4.8 | 2 | 5 | 9.3 | 9 | 7 | 3 | | | " | 321--330 | 5 | 7 | 1 | 5.2.6 | 8.7.4 | 8 | 2 | 5 | 9.3 | 9 | 7 | 3 |14 | 6 | 1:0.43 12 | 331--340 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 8.3 | 9 | 8 | 2 | | | " | 341--350 | 5 | 7 | 1 | 6 | 8.4 | 8 | 5.2 | 5 | 9.3 | 9 | 7 | 3 |15 | 5 | 1:0.33 13 | 351--360 | 5 | 5.7 | 1 | 6 | 8.4 | 8 | 5.2 | 5 | 3 | 9 | 7 | 3 | | | " | 361--370 | 5 | 7 | 6.1 | 6 | 4 | 8 | 5.2 | 3.2.5 | 9.3 | 9 | 6 | 4 |13 | 7 | 1:0.54 14 | 371--380 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 3 | 7.4.3.9 | 8 | 2 | | | " | 381--390 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 9.3 | 4.7.3.9 | 7 | 3 |15 | 5 | 1:0.33 15 | 391--400 | 5 | 5.5.7 | 1 | 3.6 | 8.4 | 8 | 3.2 | 5 | 8.3 | 9 | 5 | 5 | | | " | 401--410 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 7.3 | 6.5.3.9 | 7 | 3 |12 | 8 | 1:0.67 16 | 411--420 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 3 | 9 | 9 | 1 | | | " | 421--430 | 5 | 7 | 1 | 6 | 4 | 8 | 2 | 5 | 3 | 4.7.4.9 | 9 | 1 | | | " | 431--440 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 3 | 5.7.3.9 | 8 | 2 |26 | 4 | 1:0.15 17 | 441--450 | 5 | 7 | 1 | 6 | 4 | 4.8 | 2 | 5 | 4.3 | 3.5.9 | 7 | 3 | | | " | 451--460 | 5 | 7 | 1 | 3.6 | 4 | 5.4.8 | 2 | 5 | 9.3 | 9 | 7 | 3 | | | " | 461--470 | 5 | 7 | 1 | 6 | 4 | 8 | 2 | 5 | 3 | 9 |10 | 0 |24 | 6 | 1:0.25 19 | 471--480 | 5 | 7 | 1 | 6 | 8.4 | 8 | 2 | 5 | 3 | 9 | 9 | 1 | 9 | 1 | 1:0.11 --------+-----------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+---+---+---+---+-------- | | | | | | | | | | | | | | | | | | 5.6 | 5.6 | 4.5.6.7.8.9 | 4.5.6.7.8.9 | 1.2.3.4.5 | 1.2.3.4.5 | 2.3.4.5.6.7 | 2.3.4.5.6.7 | 3.4.5.6.7.8 | 3.4.5.6.7.8 | | | | | | +--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+---+---+---+---+-------- 19 | 1--10 | 5 | 6 | 4 | 9 | 1 | 5 | 3.7.2 | 7 | 3 | 8 | 9 | 1 | 9 | 1 | 1:0.11 ========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========

The data of table 6 indicate for this problem only three pronounced reactive tendencies: (a) As the initial tendency, the choice of the second box from the right end. This proved surprisingly weak, in view of the animal's long training on problem 2, and it disappeared quickly. (b) Choice of the end boxes, and (c) direct choice of the right box.

For this, as for the other problems, extreme differences in method and in time and degree of success appear for the different settings. Thus, while settings 1, 2, 3, 6, 7, and 10 proved to be easy, settings 4, 5, 8, and 9 were evidently more difficult.

From the first this problem promised to be much easier for Sobke than problem 2, and although the actual number of trials necessary for the solution is greater by sixty for problem 3 than for problem 2, comparison of the data of the tables justifies the statement that the third problem was both easier and more nearly adequately solved than the second. This is not surprising when the nature of the two problems is considered, for whereas problem 2 requires choice by perception of the relationship of secondness from the right end of the group, problem 3 requires, instead, the choice of the end member of the group each time, with the additional variation of alternation of ends. Now as it happens, the end member is easily selected by the monkey, and it appears further that alternation was relatively easy for Sobke to acquire. Consequently, the combination of end and alternation proved easier than the choice of the second from the right end of the group.

The above statements are supported by comparison of the curves of learning. The curve for problem 2, figure 19, is extremely irregular; that for problem 3, figure 20, much more regular. Similarly, the daily ratios of right to wrong choices as exhibited in tables 5 and 6 indicate smaller variations for the third problem than for the second.

Sobke made ten correct first choices in the third series for July 17, but he was working very uncertainly and it seemed rather a matter of good luck than good management that he succeeded in presenting this perfect series: For this reason and also because it did not seem feasible to have Sunday intervene between the final and perfect regular series and the control series, an additional regular series was given on July 19, in which, as the table indicates, a single mistake occurred, in trial 5. The monkey was working perfectly. The series of trials required only ten minutes, and it was evident that carelessness and eagerness to obtain food were chiefly responsible for the mistake.

The control series given on July 19 immediately after the series just described resulted similarly in one failure and nine successes. The choices were made easily and with certainty, and the only mistake, that of setting 7, was apparently due to carelessness.

This excellent showing for the control series wholly justifies the comparison of problems 2 and 3 as to difficultness, made above. Whereas in both problems 1 and 2 the control trials caused confusion, in the case of problem 3, they did not essentially alter the behavior of the animal. The fact seems to be that for this problem the particular setting is of relatively little importance; while turning alternately to the extreme left and the extreme right is of prime importance. That Sobke had the idea of alternation or of the end box, there seems no more reason for insisting than that he had the idea of secondness from the right end in problem 2. It is possible, even probable, that these ideas existed rather vaguely in his consciousness, but there is obviously no necessity for insisting that the solution of the problems depended upon them.

Problem 4. Middle

As the available time for the continuation of the experiment was limited, it was decided to proceed with work on problem 4 immediately upon the completion of problem 3, and on July 20, the problem of the middle door was presented to Sobke. Since it was anticipated that this sudden change would confuse and discourage him greatly, the only form of punishment administered was the momentary lowering of the entrance door of the wrong box. As in the previous problem, he was aided after ten successive wrong choices. As might have been anticipated, he persistently entered the end boxes of the groups, and this in some instances probably would have been kept up for many minutes had not the experimenter lured him into the right box by slightly raising the exit door. In the first series, he had to be aided in five of the ten trials. The total time for the series was forty-five minutes, the total number of choices, eighty-eight. In the second series, he was aided in four of the trials. The total time required was seventy-two minutes, and the total number of choices was seventy-six.

Throughout the first series, Sobke worked hard, but with evidently increasing dissatisfaction. He clung persistently to his acquired tendency to choose the end boxes, and after each trial he returned less willingly to the starting point. Up to this time his attitude toward the experimenter had been perfectly friendly, if not wholly trustful. But when on July 21 he was brought into the apparatus for the second series, he exhibited a wholly new form of behavior, for instead of attending diligently to the open doors and devoting his energies to trying to find the right box, he instead, after gazing at them for a few seconds, turned toward the experimenter and jumped for him savagely, throwing himself against the wire netting with great force. This was repeated a number of times during the first two or three trials, and it occurred less frequently later in the series. Since nothing unusual had happened outside of the experiment room, the suggested explanation of this sudden change in attitude and behavior is that the monkey resented and blamed on the experimenter the difficulty which he was having in obtaining food.

From this time on until the end of my work, Sobke was always savage and both in and out of the apparatus he was constantly on the watch for an opportunity to spring upon me. Previously, it had been possible for me to coax him into the apparatus by offering him food and to return him to his cage by walking after him. But on and after the twenty-first of July, it was impossible for me to approach him without extreme risk of being bitten.

Doctor Hamilton when told of this behavior, reported that several times monkeys have shown resentment toward him when they were having trouble in the experiment. I therefore feel fairly confident that I have not misinterpreted Sobke's behavior. When on July 22 I gave Sobke an opportunity to enter the apparatus, he refused, and it was impossible to lure him in with food. Two hours later, having waited meantime for his breakfast, he entered readily and worked steadily and persistently through his third series of trials, but in no one of these trials did he choose correctly. Neither on this day nor the following did he exhibit resentment while at work. He apparently had regained his affective poise and was able to attend as formerly to the task of locating his rewards.

During these first three series, although the ratio of right to wrong choices stood 0 to 10, there occurred a marked reduction in the number of trials in which aid was necessary as well as in the total number of choices, and on July 23 correct reactions began to appear. Improvement during the next hundred trials was steady and fairly rapid, and on July 31, a record of seven right to three wrong trials was obtained. This was surprising to the experimenter, as well as gratifying, since he was eager to have the animal complete this problem before work should have to be discontinued.

Everything went smoothly until August 2, when my assistant, who had been left in charge of the experimental work for a week, attempted to increase the number of trials per day to two series. Sobke apparently was not quite ready for this increase in the amount of his day's labor and refused to work at the end of the first series. In this series he did less well than on the previous day. The following day, August 3, unfortunately and contrary to the wishes of the experimenter, the laboratory was painted and there was necessarily considerable disturbance because of the presence of the workmen, and in addition, the pervasive odor of fresh paint. Sobke chose still less successfully on this date, and on August 4, he refused to work after the eighth trial. It is true that during these bad days the total number of choices steadily diminished while the successes, also, diminished, or at best, failed to increase. When on August 9, I returned to the laboratory to take charge, I found that Sobke was no longer trying to solve the problem as when I had gone away. His attitude had changed in that he had become indifferent, careless, and obviously discouraged with his task.

TABLE 7

Results for Sobke, P. rhesus, in Problem 4

========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+======== | No. | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | | | | | Ratio Date | of | | | 1.2.3.4 | | | 1.2.3.4.5 | | | 3.4.5.6 | | R | W | R | W | of | trials | 2.3.4 | 5.6.7.8.9 | 5.6.7 | 7.8.9 | 4.5.6.7.8 | 6.7.8.9 | 1.2.3 | 2.3.4.5.6 | 7.8.9 | 6.7.8 | | | | | R to W --------+-----------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+---+---+---+---+-------- | | | | | | | | | | | | | | | | July | | | {5.9.5.5 | {1.7.1.3 | {9.7.9.7 | | {1.9.3.1 | | {6.3.2.6 | | | | | | | 20 | 1- 10 | 2.4.2.4.3 | {5.9.5.6 | {1.7.1.7 | {7.9.7.9 | {8.4.8.4 | {9.2.9.3 | 3.1.3.2 | {3.6.3.2 | {9.3.4.3 | {8.6.6.8.6 | 0 |10 | 0 |10 | 0:10.00 | | | {5.8.7* | {1.7.4* | {7.7.8 | {4.6 | {9.1.5* | | {6.3.4* | {3.9.3.6 | {8.6.8.6.7 | | | | | | | | | | | | | | | | | | | | | | | | | | {7.9.7.7 | {4.8.5.5 | {1.4.3.2 | | | {3.9.3.8 | | | | | | 21 | 11- 20 | 2.3 | {5.6.5.5 | {1.2.7.1 | {7.9.7.7 | {8.4.8.4 | {8.9.1.9 | 3.1.2 | {6.2.3.2.6 | {4.3.3.5 | 6.7 | 0 |10 | 0 |10 | 0:10.00 | | | {9.5.5.7 | {7.3.7.4 | {9.7.8* | {5.4.6* | {1.9.5* | | {3.5.2.4 | {3.4.6* | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {3.7.4.8 | | | | | | 22 | 21- 30 | 2.3 | 5.6.5.6.7 | 1.7.4 | {7.9.7 | 4.7.4.6 | {1.4.6.3 | 3.1.2 | 5.2.6.4 | {4.3.5.8 | 6.6.7 | 0 |10 | 0 |10 | 0:10.00 | | | | | {7.7.8 | | {2.7.5 | | | {3.7.6* | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {5.4.7.4 | | | | | | 23 | 31- 40 | 2.4.3 | 5.6.8.7 | 1.7.4 | {7.7.7.7 | 4.7.6 | 2.7.5 | 3.1.2 | 6.4 | {7.5.4.3 | 7 | 1 | 9 | 1 | 9 | 1: 9.00 | | | | | {7.7.8 | | | | | {7.3.6 | | | | | | | | | | | | | | | | | | | | | | 24 | 41- 50 | 3 | 5.6.7 | 1.6.4 | 7.7.7.8 | 4.7.6 | {2.7.6.4 | 3.2 | 6.5.4 | 5.3.8.6.6 | 7 | 1 | 9 | 1 | 9 | 1: 9.00 | | | | | | | {2.7.3.8 | | | | | | | | | | | | | | | | {9.6.5* | | | | | | | | | | | | | | | | | | | | | | | | | 26 | 51- 60 | 4.3 | 6.5.7 | 2.7.4 | 7.8 | 6 | {6.4.2.7 | 3.2 | {6.5.3.5.2 | 7.6 | 7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | {4.8.6.5 | | {6.5.6.4 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {4.7.3.7 | | | | | | | | | 27 | 61- 70 | 3 | 6.5.7 | 2.5.4 | 7.7.8 | 5.7.6 | {4.6.1.4 | 2 | 6.5.4 | 5.7.6 | 6.7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | {7.3.5 | | | | | | | | | | | | | | | | | | | | | | | | | 28 | 71- 80 | 3 | 7 | 6.5.4 | 7.8 | 5.4.7.6 | 2.7.6.5 | 2 | 5.5.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 29 | 81- 90 | 3 | 6.5.7 | 2.4 | 7.7.8 | 5.4.6 | {2.7.7.6 | 2 | 4 | 5.4.7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | {2.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 30 | 91-100 | 3 | 7 | 2.6.5.4 | 7.8 | 6 | 5 | 2 | 5.4 | 5.4.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 31 | 101-110 | 3 | 7 | 2.4 | 7.8 | 6 | 5 | 2 | 4 | 7.6 | 7 | 7 | 3 | 7 | 3 | 1: 0.43 August | | | | | | | | | | | | | | | | 2 | 111-120 | 3 | 7 | 6.5.7.6.4 | 7.8 | 6 | 4.2.7.6.5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 3 | 121-130 | 3 | 6.5.7 | 7.6.5.4 | 7.8 | 7.6 | 5 | 2 | 6.5.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 4 | 131-140 | 3 | 7 | 6.5.7.6.4 | 7.8 | 6 | {2.7.6.4 | 2 | 6.4 | 3.5.4.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 | | | | | | | {8.7.6.5 | | | | | | | | | | | {2.4.4.4 | | | | | | | | | | | | | | 5 | 141-150 | {2.4.4.2 | 6.5.7 | {2.7.6.7 | 8 | 7.6 | {2.8.7.6 | 3.2 | 6.4 | 7.6 | 8.7 | 1 | 9 | 1 | 9 | 1: 9.00 | | {4.3* | | {5.4 | | | {8.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 6 | 151-160 | 2.4.4.3 | 7 | 2.6.5.4 | 7.8 | 7.6 | 7.6.5 | 2 | 6.4 | 6 | 7 | 4 | 6 | | | | | | | | | | | | | | | | | | | | | {4.4.2.4 | | | | | | | | | | | | | | " | 161-170 | {4.2.4.2 | 7 | 6.5.4 | 7.8 | 7.6 | 7.6.5 | 3.2 | 5.4 | 7.6 | 7 | 2 | 8 | 6 |14 | 1: 2.33 | | {4.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 7 | 171-180 | 4.3 | 7 | 6.5.4 | 8 | 7.6 | 5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | | | | | | | | | | | | | | | | | | | " | 181-190 | {4.2.4.4 | 7 | 7.6.5.4 | 7.8 | 6 | 6.5 | 2 | 6.5.4 | 7.6 | 7 | 4 | 6 | 9 |11 | 1: 1.22 | | {2.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 9 | 191-200 | 3 | 7 | 5.4 | 8 | 8.7.6 | 6.5 | 2 | 6.5.4 | 7.6 | 8.7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 10 | 201-210 | 3 | 7 | 2.5.4 | 7.8 | 7.6 | {2.8.7.6 | 2 | 6.5.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | {8.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 11 | 211-220 | 3 | 7 | 6.5.4 | 7.8 | 6 | {7.6.4.3 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 | | | | | | | {2.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 12 | 221-230 | 3 | 7 | 2.4 | 7.8 | 6 | 7.6.5 | 2 | 6.5.4 | 8.7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 19 | 231-240 | 3 | 7 | 2.4 | 7.8 | 6 | 5 | 2 | 6.4 | 8.7.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 | | | | | | | | | | | | | | | | 20 | 241-250 | 3 | 7 | 5.4 | 8 | 7.6 | {2.4.1.2.7 | 3.2 | 6.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | {8.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 21 | 251-260 | 3 | 7 | 6.5.4 | 7.8 | {7.4.5.4 | {6.4.3.2 | 2 | 6.5.4 | 8.7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | {8.7.6 | {7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 23 | 261-270 | 3 | 7 | 6.5.4 | 7.8 | 6 | 6.5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 24 | 271-280 | 3 | 7 | 6.4 | 7.8 | 7.6 | 2.5 | 2 | 4 | 7.4.3.8.7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 25 | 281-290 | 3 | 7 | 2.5.4 | 8 | 7.6 | 5 | 2 | 6.4 | 7.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 26 | 291-300 | 3 | 7 | 6.5.4 | 8 | 7.6 | 7.6.5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 27 | 301-310 | 3 | 7 | 2.6.5.4 | 8 | 7.6 | 5 | 2 | 6.5.4 | 7.5.4.9.8.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 28 | 311-320 | 3 | 7 | 2.5.4 | 8 | 6 | 9.8.7.5 | 2 | 3.4 | 8.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 ========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========

I immediately set about reinstating the former attitude by lessening the number of trials and the punishment, and by increasing the value of the reward, but my best efforts, continuing up to August 28, failed markedly to improve the condition. The number of correct choices did somewhat increase, but at no time did the animal attain the degree of success which he had achieved as early as July 31 in the eleventh series of trials.

During the last two weeks of experimentation, all possible efforts were put forth to discover the best combination of rewards and punishments. Punishment was varied from 0 to confinement of sixty seconds, and many kinds of food in different amounts were tried as rewards, but in spite of everything Sobke failed to improve markedly. From time to time, notably on August 12 and 21, he exhibited peculiarly strong resentment toward me and repeatedly attempted to attack me.

The outcome of my experiments with problem 4 is peculiarly interesting in that it indicates the importance of a favorable attitude toward the work and the extreme risk from disturbing or discouraging conditions. It seems not improbable that had the work progressed without change in experimenter, or method of procedure, and above all without the disturbance of the painting, Sobke might have solved problem 4 within a few days. This is by no means certain, however, for in problems 2 and 3 the ratio of right to wrong choices instead of increasing steadily increased very irregularly.