1. the act of spreading ideas, knowledge, or beliefs to a wider audience

"The great work of the present for every man, and every organization of men, who would improve social conditions, is the work of education — the propagation of ideas."

- Henry George (1839 - 1897)

2. breeding plants or animals to create new specimens from the originals

"Once we are self-aware, we must choose purposes and principles to live by; otherwise the vacuum will be filled, and we will lose our self-awareness and become like groveling animals who live primarily for survival and propagation."

- Stephen Covey (1932 - 2012)