English verbs form the past tense two ways. Regular verbs ad “ed” to the end of the verb. For example, “work” becomes “worked.” Irregular verbs, sometimes called “strong” verbs, require internal changes to form the past tense. For example, “sing” becomes “sang” and “do” becomes “did.”
Irregular verbs are becoming regularized over time. For example, “help” is now a regular verb, though its past tense was once “holp.” (I’ve heard that you can still occasionally hear someone use archaic forms such as “holp” and “holpen.”)
What I find most interesting about this change quantifying the rate of change. It appears that the half-life of an irregular verb is proportional to the square root of its frequency. Rarely used irregular verbs are most quickly regularized while commonly used irregular verbs are the most resistant to change.
Exceptions have to be constantly reinforced to keep speakers from applying the more general rules. Exceptions that we hear less often get dropped over time. So it’s not surprising that half-life is a decreasing function of frequency. What is surprising is that that half life is such a simple decreasing function, a constant over square root.
I’m skeptical of what Lieberman has to say, and would like to see the data. The key word in that article is “about.” Given the function of irregular forms in language, I doubt there’s much mathematical precision in terms of when or even if an irregular form should get regularized. I suspect that some irregular forms are immune from the process — the value of having an irregular past tense is simply too great for the language to permit it to be lost for common verbs.
This value of irregular forms seems to have completely escaped Lieberman’s attention. He seems to view them merely as relics that survive through sheer repetition. Languages operate more like market forces or evolutionary theory in dropping less useful appendages and adapting and developing items from contact with other languages. For example, high school grammar teachers are powerless to dissuade newer generations from using newer ways of speaking that reflect the latest linguistic changes. It’s like building dikes around New Orleans. Languages are constantly changing and they’re not pack rats — they don’t keep useless things. There’s a reason why English has such an extensive vocabulary, such as why we have “ruminate,” “ponder,” “consider” and “think.” If something is useless, it disappears. If something new is needed, it can be created from within the language or borrowed from another. The irregular verb forms enhance listening comprehension, but we can only afford to use them with the most common verbs.
It appears that multiple related articles about this work were published around the same period:
Harvard Gazette
Nature (apparently the original article)
Discover
The NIH” National Library of Medicine–looks like a slightly earlier version.
Did you mean to say “inversely proportional”? That would mean that more frequent verbs are regularized faster. The paper itself says the rate of change is inversely proportional, but that’s different from the half-life. Large half-lives mean slower rates of change.
You’re right. I removed the word “inversely.”
Interesting. I live in Southern California but am originally from the Midwest. I’ve noticed for several years that people here are more likely to substitute the irregular past participles with the simple past form than people from farther East.
The theory is that verbs that are uncommon are more likely to be regularized – I’m not sure that’s always the case, as these are regularized verbs that I have personally heard within the last five years:
I have *saw instead of I have seen (licensed SoCal attorneys)
If I had *knew instead of If I had known
Has *flew instead of Has flown
Has *sang instead of Has sung (Linguist Steven Pinker / my choir director)
Has *ran instead of Has run
Has *came instead Has come
“Have *went” instead of “Have *gone” is ubiquitous – I once heard NPR’s Terry Gross say it. drank instead of drunk is also ubiquitous. These are common verbs.