- wave propagation
- propagation of energy by waves,
- two-way wave propagation
- one-way propagation of heat energy (from warm to cold).
For when propositions are denied, there is an end
of them, but if they bee allowed, it requireth a
new worke. The Essais of Sr. Francis Bacon, London, 1612
The further a society drifts from the truth, the more it will hate those who speak it. George Orwell
Nothing is created by coincidence, rather there is reason and necessity for everything. Leukippus, 5th Century BC.