But it seems to me, Socrates, that these things are not the things to blame.
[Since this sentence is short, I had planned to translate it with the next one. But even the short sentences don't translate easily. Despite all the hoops of syntax that follow below, the meaning of the sentence seems to be pretty clear. Cephalus thinks that those who complain about old age are not singling out what is actually blameworthy.
Literally, the sentence reads as follows: "But it seems to me, Socrates, these not the blame to blame." The choices the translator must make are made clear by this literal rendition. One has to decide what the antecedent of "these" is, and one also has to decide how to make "not the blame to blame" intelligible. In particular, the ambiguity is the result of (1) the word houtoi, which I've translated "these things," and (2) the use of the infinitive aitiasthai, "to blame."
Let's look at the second problem first because I think it will make the first decision clearer. We have in the second part of the sentence a subordinate clause in which the infinitive occurs. Normally, one might expect the subject of the subordinate clause to be in the accusative (see Smyth, sec. 1975). In this sentence, the subject looks to be outoi, which is nominative. I think this -- with the lack of a relative pronoun -- indicates that the infinitive is supposed to remain in the infinitive mood. Thus, we need to include "to blame" somewhere in the translation.
(It could be that the subject of the infinitive is aition, "the blameworthy," which is in the accusative case. Then the clause might read "these men do not blame the blameworthy." The problem with this is that the negative particle precedes the noun aition not the infinitive (verb) aitiasthai. For this reason, I don't think that translation is as good as the one I've chosen.)
This leads us back to the first issue of finding the antecedent of outoi. We have two choices. We could translate it as "these men" or "these things." If we translate it "these men," then the sentence needs to read ". . . these men not the blame to blame," which doesn't make sense, and it isn't clear what we could add that would make it sensible. However, most translators choose to go this route, which counts for something against my decision. For example, Reeve says, "I don't think they blame the real cause."
But if we translate "these things," the we get ". . . these things not the blame to blame," and it seems acceptable (which is a judgment call) to add "are" in order to get "these things are not the blame to blame." Yet another judgment call is taking "the blame" substantivally to mean "the blamed (or blameworthy) things," and the result is that, in passable English, we get "these things are not the things to blame."
Two last notes. First, it could be the case that since Plato is writing dialogue for the character Cephalus, he's mimicking how a person might actually speak, in which case the spoken sentences may not have the perfect syntax we'd expect from prose. We often say things that would be difficult to decipher if written down but make good sense when spoken. Context is important in these cases.
Second, the usually more-literal-than-thou Bloom goes for the idiomatic in this sentence; his translation is "these men do not put their fingers on the cause."]