I’m studying from Reading Greek and at 1D, it seems to me like both of them mean exactly “it is sinking.”.What exactly is the difference between the two?
It must be confusing to find both verbs so close together. In this text there is no difference in meaning.
There are many uses in this section of the prefix “κατα” and I suspect that “καταδύει” is used simply so that in class it will be easier to work out the meaning of the simple verb, “δύει”.
In other contexts there are differences see https://logeion.uchicago.edu/καταδύω and https://logeion.uchicago.edu/δύω
Don’t worry about possible shades of meaning in this text. But always ask if you are unsure of things. This is a good question which I am sure has puzzled many in the past.
(I think when I read this text first of all a long time ago “κατα” was explained as “thoroughly” or “completely” but that still doesn’t explain why the two forms are used consecutively.)
Hi, just to add, a verb with prefix usually does have a meaning different to the simple form, but change of sense is not the only reason for a Greek author using one or the other form. e.g. there is a relationship between the usage (or not) of certain prefixes and the aspect of the verb (see e.g. Duhoux 2000 s137g, the best book on the Grek verb for questions like this: it’s in French).
However what I suspect is happening here (where the simple form is used shortly after the prefixed form) is a phenomenon I’ve seen a bit in Greek (and other languages: it probably happens in English too, but I haven’t thought much about it) where a prefixed verb, when echoed later in the text, is simplified down to the form without a prefix. There is definitely a discussion of this in a commentator on one of Plato’s dialogues, and if you dig around you’ll find it: I just can’t remember this morning where that discussion is, sorry!
Cheers, Chad