What kind of lines are these? — the meticulous reader will ask.
Plot lines? Behavior lines? Defense lines? Life lines on the author's two hands — left and right? Or is this name in honor of the St. Petersburg streets on Vasilievsky Island? Oh no.
Just lines. Probably straight ones. At least, that's what the author's inner eye, which is always right, tells him. And you now hold in your hands one of these two lines, undoubtedly parallel. In some places, however, they intersect. And in others, they don't, as they taught in school. Because a universe in which only one truth exists is impossible.
For technical reasons, as they say.