This is more of a documentary post than anything, though it might be interesting tidbits for those of us who - like Emily and I - are interested in language. Our new child, Joseph (our first), is
approximately four months old at the time of this writing. We have discovered that he has several utterances/vocalizations which recur pretty exactly, according to a formula. These sounds do also seem to correspond very strongly to different kinds of emotional states and/or stimuli Joseph encounters. A brief catalog, spelled phonetically:
"Ghee" - Used to express probable worry, concern.
"Naing" - Used in the throes of a tantrum. Appears to express extreme dissatisfaction.
"Agoo" - Somewhat more mysterious. Seems to imply pleasant surprise? The first of these three to appear.
I will add more later, so this will be something of an ongoing effort to catalog all his "words" before he begins to make real ones.
Sidenote: the meaning of these phrases was of course determined by Emily and I prior to Joseph's actually being able to articulate what he feels they signify. In the absence of a sufficiently robust theory of universal grammar, we may suppose that these are somewhat unique to this baby, though perhaps they share similarities with other babies of English-speaking couples in the 21st century. Nevertheless, the strong correlation with visible external states (crying, smiling, etc) seems to imply that we cannot be far off in guessing the import of these sounds. Considering the remarkable simplicity and ease of use inherent in these sounds (probably not full symbols - they are direct results of mental states, not communications thereof), it would behoove a science fiction author and worldbuilder to do research at some point into what extent such directness can be found in natural/synthetic languages.