But maybe it's "-летие"?
After 19 years, the 20th anniversary arrives. But it's not quite clear with "самом в себе" (itself). Let's assume that zero is a thing in itself. But what about two?
Знание некоторых закономерностей освобождает от изучения многих фактов.
Мечты сбываются рано или поздно, так или иначе.