While checking notecards today, I came across a few modern examples of parablepsis and unintentional scribal changes — the kind of stuff normally discussed in introductions to textual criticism.((For example: Emanuel Tov, Textual Criticism of the Hebrew Bible (Minneapolis, MN: Fortress, 2012), 227ff.; Paul D. Wegner, A Students Guide to Textual Criticism of the Bible: Its History, Methods, and Results (Downers Grove, IL: IVP, 2006), 44.)) It's nice when you have the opportunity to test your solutions to text-critical problems by speaking with the actual scribes.
The first one is a clear example of an unintentional variant created by phonological similarity — the student wrote ο rather than ω. The neat thing is that the student was copying out of the book but made an error of hearing. She read θέλω, turned to her notecard, said the word to herself correctly as "thĕlō," and then wrote θελο. So this was a confusion of phonologically similar letters from someone copying a written text and pronouncing the word only in her mind, not aloud.
This is a fun sort of parablepsis. The student saw διδάσκω in the vocab list and began to write the first part of the word, looked back at his book, and his eye fell on the last portion of the previous word, γράφω. So διδάσκω + γράφω = διδάφω.
One more: this time the issue is a blend of graphic similarity and interference of the native language.
The word is supposed to be βλέπω (blĕpō). The fact that π makes the sound of an English p is obviously an issue here, similar to the first example above. But this one has an added element. I don't think the student would have made this mistake if rho (ρ), a similar looking letter to English p, were not a part of the Greek alphabet.
Even if Greek ρ makes a different sound than English p, rho provides some warrant for writing ρ in a Greek word to represent the sound of an English p.
I wanted to give these students extra credit for their scribal errors because they are just so fascinating.