What about the heart-warming stories of human-ape understanding? Human handlers interacted with the apes for thousands of hours, and occasionally the human interpretation of a string of signs would stand out as interesting. But, this makes the interesting sign combinations look more like generous interpretations of anecdotes that were cherry-picked, or fed to the ape by human handlers, and not a conscious thinking pattern.
What’s more, the meaning of the signs was very easy to over-interpret. Is
water bird the intellectual combination of two concepts to indicate a waterfowl? Or is it just rote repetition that a lake and a bird are nearby, combined with generous and wishful human interpretation? Studies in the field generally focused on picking unusual instances out of thousands of hours footage, rather than systematically studying whether apes expressed meaningful ideas. When Terrace did this, he found that interesting sentences began to look like drops in the ocean.
Most of that footage demonstrated the apes producing word salads that contained signs for food or affection they desired. Usually these sentences were very short, and in
no sense grammatical. Terrace noted that nearly all Nim’s sentences were two or three words long; extended sentences were very rare. The general pattern was:
Nim or
me followed by
eat,
play,
tickle,
banana,
grape, or the like. Human children begin with short sentences. But they rapidly develop the ability to form longer sentences, conveying meaningful thoughts, asking questions, and expressing new ideas. Nim never did any of these things.
Nim once formed a sixteen-word sentence:
give orange me give eat orange me eat orange give me eat orange give me you. If that sounds to you more like the nonsense babbling of a parrot, or what your dog might say to you if he saw that you had an orange, and much less like the thoughts of a child, you can see the problem.
