Animal Intelligence / The International Scientific Series, Vol. XLIV.

by George John Romanes

Although this account, as I have said, borders on the incredible, I have allowed it to pass, because up to a certain point it is, as I have also said, corroborated by an observation communicated to me by my friend Dr. Klein, F.R.S.

Dr. Klein satisfied himself that the cat he observed had established a definite association between crumbs already sprinkled on the garden walk, and sparrows coming to eat them; for as soon as the crumbs were sprinkled on the walk, the cat used to conceal himself from the walk in a neighbouring shrubbery, there to await in ambush the coming of the birds. The latter, however, showed themselves more wide awake than the cat, for there was a wall running behind the shrubbery, from the top of which the birds could see the cat in his supposed concealment, and then a long line of sparrows used to wait watching the cat and the crumbs at the same time, but never venturing to fly down to the latter until the former, wearied with waiting, went away. In this case the reasoning observation of the cat—'crumbs attract birds, therefore I will wait for birds when crumbs are scattered'—was as complete as in the case of Dr. Frost's cat, but the reasoning in the latter case seems to have proceeded a stage further—'therefore I will scatter crumbs to attract birds.'

Now, in the face of the definite statement made by Dr. Frost, that his cat did advance to this further stage of reasoning, I have not felt justified in suppressing his remarkable observation. And, as lending still further credence to the account, I may quote the corroborative observation of another correspondent in 'Nature,' which is of value because forming an intermediate step between the intelligence displayed by Dr. Klein's cat and that displayed by Dr. Frost's. This correspondent says:—

A case somewhat similar to that mentioned by Dr. Frost, of a cat scattering crumbs, occurred here within my own knowledge. During the recent severe winter a friend was in the habit of throwing crumbs outside his bedroom window. The family have a fine black cat, which, seeing that the crumbs brought birds, would occasionally hide herself behind some shrubs, and when the birds came for their breakfast, would pounce out upon them with varying success. The crumbs had been laid out as usual one afternoon, but left untouched, and during the night a slight fall of snow occurred. On looking out next morning my friend observed puss busily engaged scratching away the snow. Curious to learn what she sought, he waited, and saw her take the crumbs up from the cleared space and lay them one by one after another on the snow. After doing this she retired behind the shrubs to wait further developments. This was repeated on two other occasions.[257]

Taking, then, these three cases together, we have an ascending series in the grades of intelligence from that displayed by Dr. Klein's cat, which merely observed that crumbs attracted birds, through that of the cat which exposed the concealed crumbs for the purpose of attracting birds, to that of Dr. Frost's cat, which actually sprinkled the crumbs. Therefore, although, if the last-mentioned or most remarkable case had stood alone, I should not have felt justified in quoting it, as we find it thus led up to by other and independent observations, I do not feel that I should be justified in suppressing it. And, after all, regarded as an act of reason, the sprinkling of crumbs to attract birds does not involve ideas or inferences very much more abstruse or remote than those which are concerned in some of the other and better corroborated instances of the display of feline intelligence, which I shall now proceed to state.

In the understanding of mechanical appliances, cats attain to a higher level of intelligence than any other animals, except monkeys, and perhaps elephants. Doubtless it is not accidental that these three kinds of animals fall to be associated in this particular. The monkey in its hands, the elephant in its trunk, and the cat in its agile limbs provided with mobile claws, all possess instruments adapted to manipulation, with which no other organs in the brute creation can properly be compared, except the beak and toes of the parrot, where, as we have already seen, a similar correlation with intelligence may be traced. Probably, therefore, the higher aptitude which these animals display in their understanding of mechanical appliances is due to the reaction exerted upon their intelligence by these organs of manipulation. But, be this as it may, I am quite sure that, excepting only the monkey and elephant, the cat shows a higher intelligence of the special kind in question than any other animal, not forgetting even the dog. Thus, for instance, while I have only heard of one solitary case (communicated to me by a correspondent) of a dog which, without tuition, divined the use of a thumb-latch, so as to open a closed door by jumping upon the handle and depressing the thumb-piece, I have received some half-dozen instances of this display of intelligence on the part of cats. These instances are all such precise repetitions of one another, that I conclude the fact to be one of tolerably ordinary occurrence among cats, while it is certainly very rare among dogs. I may add that my own coachman once had a cat which, certainly without tuition, learnt thus to open a door that led into the stables from a yard into which looked some of the windows of the house. Standing at these windows when the cat did not see me, I have many times witnessed her modus operandi. Walking up to the door with a most matter-of-course kind of air, she used to spring at the half-hoop handle just below the thumb-latch. Holding on to the bottom of this half-hoop with one fore-paw, she then raised the other to the thumb-piece, and while depressing the latter, finally with her hind legs scratched and pushed the doorposts so as to open the door. Precisely similar movements are described by my correspondents as having been witnessed by them.

Of course in all such cases the cats must have previously observed that the doors are opened by persons placing their hands upon the handles, and, having observed this, the animals forthwith act by what may be strictly termed rational imitation. But it should be observed that the process as a whole is something more than imitative. For not only would observation alone be scarcely enough (within any limits of thoughtful reflection that it would be reasonable to ascribe to an animal) to enable a cat upon the ground to distinguish that the essential part of the process as performed by the human hand consists, not in grasping the handle, but in depressing the latch; but the cat certainly never saw any one, after having depressed the latch, pushing the doorposts with his legs; and that this pushing action is due to an originally deliberate intention of opening the door, and not to having accidentally found this action to assist the process, is shown by one of the cases communicated to me (by Mr. Henry A. Gaphaus); for in this case, my correspondent says, 'the door was not a loose-fitting one by any means, and I was surprised that by the force of one hind leg she should have been able to push it open after unlatching it.' Hence we can only conclude that the cats in such cases have a very definite idea as to the mechanical properties of a door; they know that to make it open, even when unlatched, it requires to be pushed—a very different thing from trying to imitate any particular action which they may see to be performed for the same purpose by man. The whole psychological process, therefore, implied by the fact of a cat opening a door in this way is really most complex. First the animal must have observed that the door is opened by the hand grasping the handle and moving the latch. Next she must reason, by 'the logic of feelings'—If a hand can do it, why not a paw? Then, strongly moved by this idea, she makes the first trial. The steps which follow have not been observed, so we cannot certainly say whether she learns by a succession of trials that depression of the thumb-piece constitutes the essential part of the process, or, perhaps more probably, that her initial observations supplied her with the idea of clicking the thumb-piece. But, however this may be, it is certain that the pushing with the hind feet after depressing the latch must be due to adaptive reasoning unassisted by observation; and only by the concerted action of all her limbs in the performance of a highly complex and most unnatural movement is her final purpose attained.

Again, several very similar cases are communicated to me of cats spontaneously, or without tuition, learning to knock knockers and ring bells. Of course in both cases the animals must have observed the use to which knockers and bells are put, and when desiring a door to be opened, employ these signals for the purpose. It betokens no small amount of observation and reasoning in a cat to jump at a knocker with the expectation of thereby summoning a servant to open the door—especially as in some of the cases the jump is not a random jump at the knocker, but a deliberate and complex action, having for its purposes the raising and letting fall of the knocker. For instance, Mr. Belshaw, writing to 'Nature' (vol. xix., p. 659), says:—

I was sitting in one of the rooms, the first evening there, and hearing a loud knock at the front door was told not to heed it, as it was only this kitten asking admittance. Not believing it, I watched for myself, and very soon saw the kitten jump onto the door, hang on by one leg, and put the other fore-paw right through the knocker and rap twice.

In such cases the action closely resembles that of opening thumb-latches, but clearly is performed with the purpose of summoning some one else to open the door. Wonderful, however, as these cases of summoning by knockers undoubtedly are, I think they are surpassed by other cases in which the instrument used is the bell. For here it is not merely that cats perfectly well understand the use of bells as calls,[258] but I have one or two cases of cats jumping at bell-wires passing from outside into houses the doors of which the cats desired to be opened.[259] My informants tell me that they do not know how these cats, from any process of observation, can have surmised that pulling the wire in an exposed part of its length would have the effect of ringing the bell; for they can never have observed any one pulling the wires. I can only suggest that in these cases the animals must have observed that when the bells were rung the wires moved, and that the doors were afterwards opened; then a process of inference must have led them to try whether jumping at the wires would produce the same effects. But even this, which is the simplest explanation possible, implies powers of observation scarcely less remarkable than the process of reasoning to which they gave rise.