Posted by Neal on February 10, 2005
Adam has an unusual ability for a four-year-old: He can say both ‘th’ sounds, [θ] (as in thick) and [ð] (as in this). It’s not so much that he’s precocious in this regard as that he tends to keep his tongue a little forward in his mouth in general. So even though he makes perfect [θ] and [ð], with his tongue right between his front teeth where it needs to be, he also keeps it there for his alveolar consonants (t, d, n, s, z), so that his perfect th’s come along with a lisp and funny-sounding t’s, d’s, and n’s.
Meanwhile, Adam has been playing Mousetrap a lot during the past week, and I get to hear his perfect [θ] whenever he rolls a three. But when he rolls higher than a three, say a five, he’ll pick up his mouse, and count:
One, two, three, Thor, thive!
Where other kids are busy turning three and free into homophones just because they can’t say [θ], Adam’s taking that [θ] and going to town with it! But why is he replacing his [f] with [θ], when he doesn’t have a problem saying [f]?
It’s because his three has contaminated them. Contaminated them, I tell you! And not only is it a clear case of contamination (i.e., semantically related words becoming more similar to each other phonetically), it’s even a canonical one. According to Hock’s Principles of Historical Linguistics, “contamination occurs frequently in antonyms….” and get this, “It is also commonly encountered in the numerals” (p. 197). The first example Hock gives is from Latin, where septem ‘seven’ and decem ‘ten’ influenced an earlier Latin noven ‘nine’ to become classical Latin novem. The second example is a dialect of Greek in which the initial [h] of hepta ‘seven’ contaminates okto ‘eight’, turning it into hokto. So Adam’s following the Romans and the Greeks (not to mention the Norse) when he says “Thor” and “thive.”
Just as linguists say you shouldn’t, I tried to correct him, to undo the contamination:
Me: Adam, say “three, four, five.”
Adam: Four, five!
Me: Say “three, four, five.”
Adam: Free, four, five!
D’oh! Now the four and five are ganging up on the three and contaminating it!