The Clark and Hecht reading looked at how children learned to use the -er suffix to formulate both agent (e.g. "baker") and instrument ("cutter") nouns in English. The study found that older children had more of a grasp on these concepts, and also that all the children used various different responses to the questions.
I was very intrigued by the variety of responses, as they show how we deal with language without the hand-hold of convention; "spontaneous word
innovations," as Clark calls them. One device that children use very early on, and to a high degree, is
compounding, where one combines words to create a word that shares their meaning. We see these everywhere in English; Clark gives "doghouse" and "painkiller" as examples; we also see "dishwasher," "lawnmower," "caregiver," etc., etc. German is also infamous for its compound words; Krankenwagen, for instance, means "ambulance," literally meaning "sick (
krank) car
(wagen)." Another great example is "Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz," which means "the law for the delegation of monitoring beef labeling."
German is very closely related to Old English, which abounds with compound words. What do you call a king, the person who gives out gold and rewards in the mead-hall to his favorite thanes? Well, a bēahġifa, or "ring-giver," of course! A warrior? "Raven-feeder," since, well, ravens were said to eat the dead on battlefields. These types of words were known as
kennings, from
kenna, which means "to make known, to name." So, if you knew what these things were, in an essential way (i.e. their essential properties--that they feed ravens, or give rings) you could name them.
What is not always clear, in both -er words and compound words, is the actual mechanism of the word. For compound words, this is in the relationship between the words; If a garbage truck collects garbage, what does an icecream truck do? What, then, does a firetruck do? A dogsled isn't a sled for dogs, but a sled driven by dogs, but a doghouse is a house for dogs.
For -er words, I can understand why children would be confused; it can act as either an agent or instrument. A typewriter isn't the person who types the words, but is the instrument used to type them? Is a "chopper" a person who chops, or the instrument used to chop*? (As an aside, it's also a helicopter.) Finally, what about the comparative? "Closer," for instance, could mean "a thing that closes," "a person who closes (a deal, or a store, or a door, etc.)," or it could mean "more close"!
In light of English not really making much sense, I would say that the innovations of children are just as valid as what convention would have us say--it's just that convention's been around longer. I think it's kind of a shame, in fact, that "children consistently relinquish
their own innovations in favor of the conventional words for those meanings," as Clark points out. However, I suppose we have to reach some kind of standard.
*This makes the kitchen appliance called the "Slap Chop" particularly linguistically interesting, as it should be called the "Slap Chopper"