On the edges

Don't loss sight of the people on the edges

“And what do you really do? asked Tiffany. The thin witch hesitatied for a moment, and then: We look to ... the edges, said Mistress Weatherwax. There's a lot of edges, more than people know. Between life and death, this world and the next, night and day, right and wrong ... an' they need watchin'. We watch 'em, we guard the sum of things. And we never ask for any reward. That's important.” ― Terry Pratchett, The Wee Free Men

First Sight means that you can see what really is there, and Second Thoughts mean thinking about what you are thinking. And in Tiffany's case, there were sometimes Third Thoughts and Fourth Thoughts, although these were quite difficult to manage and sometimes led her to walk into doors -from I Shall Wear Midnight~by Terry Pratchett