The term boundary means "that which indicates the limits of anything," 1620s, from bound (n.1) + -ary. Strictly, a visible mark indicating a dividing line, a bound being the limit or furthest point of extension of any one thing. 

What are the limits of knowledge? What is the boundary of wisdom? We place boundaries on most everything. Boundaries work for understanding where one's land starts and ends. It is good to have boundaries on one's workday. All work and no play makes Jack a dull boy. Knowledge and wisdom have no boundaries unless one decides boundaries are necessary.

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Obstacles in mind, shatter the past with breathing, shards of emotions