I have elsewhere[169] expressed my opinion that, though animals may behave in ways which may tend to mislead us, they do not act with intent to deceive. A dog is described[170] as “showing a deliberate design of deceiving” because he hobbled about the room as if lame and suffering from pain in his foot. But may not this be simply due to the fact that chance experience had led to a situation through which a hobbling gait had acquired the meaning of more petting and attention than usual? To behave with deceit as a deliberate motive implies the idea that the action will be interpreted as having a significance different from that which it really has. It is only possible on the ideational plane of mental development. It implies, too, from the ethical standpoint, a conscious departure from the standard of truth. The black that is acted has conscious reference and relation to the white that is not black. Few, however, will credit animals with deceit of this fully conscious and deliberate kind. Like the fibs of little children, the apparent deceit of animals is probably merely behaviour which has been associated in experience with pleasant results.
The case of shamming sickness, quoted from K. Russ, is thus interpreted by Professor Groos.[171] And yet he adds, “When we see deception used so effectively to serve practical ends, examples of which are very common, it can hardly be doubted that there is in all probability more consciousness of shamming in play than we have any means of demonstrating.” And elsewhere in the same work he observes,[172] “Many a grown animal still takes pleasure in the mock combats that he learned in youth. From a psychological point of view this phenomenon is especially noteworthy, from the fact that the adult animal, though already well acquainted with real fighting, still knows how to keep within the bounds of play, and must therefore be consciously playing a _rôle_, making believe.” I fail, however, to see the justification for the “therefore.” Surely the difference of behaviour in this example, and in other such examples, is sufficiently explained as the outcome of diverse situations, without having recourse to anything so psychologically complex as the conscious self-illusion of make-believe--interesting and important as this is in the psychology of children. To suppose that a monkey who nurses a bit of blanket has any ideas about its being a make-believe baby is _not_ to interpret the behaviour of animals in accordance with the canon we have adopted for our guidance.