In the giver chapter 18 what does the river symbolize

The river forms a border of the community before continuing on to Elsewhere. As a border, the river comes to symbolize escape—crossing the river means leaving the community. Because it takes the life of the four-year-old Caleb, the river also symbolizes the danger inherent in that escape.

Because writing on paper is said to engrave what your writing down into your brain therefore writing your thoughts is better than speaking them.