Ex:

In sentences like the above..
In cases like the above
In cases like Paul's case
and etc..

I am assuming that we don't put the article "the" after "in" in the cases above because they (sentences, cases, and etc) mean ANY of them that resembles the previously mentioned example/form. Is that correct? Or is it just an idiom?

I ask this because I want to have the right logic in mind. I tend to want to put the article in similar sitatuations because they refer to specific forms of the thing we are talking about.

Thanks in advance.