Hi. Here I see two reasons not to take them as substantives. First, if it were a general statement about "hearing ones" or "those who hear", you would regularly have the article. And also, the most natural reading is to take the subject of βλέπωσιν and συνιῶσιν as referring back to τοῖς λοιποῖς, in which case, the participles would have to be circumstancial.
As to deciding what kind of circumstancial participle, that's determined by the context. There are certain particles that make the meaning more precise, for example καίπερ indicates a concessive meaning, but these aren't always used, and in the end it comes down to context.
Last edited by modus.irrealis
on Sun Feb 15, 2009 1:01 am, edited 2 times in total.