"The most powerful weapon on earth is the human soul on fire"

"It is only when they go wrong that machines remind you how powerful they are"

"Powerful indeed is the empire of habit"

"The most valuable possession you can own is an open heart. The most powerful weapon you can be is an instrument of peace"

"Machines were, it may be said, the weapon employed by the capitalists to quell the revolt of specialized labor"

"The best weapon against an enemy is another enemy"

"The human race has one really effective weapon, and that is laughter"

"Non-violence is the greatest force at the disposal of mankind. It is mightier than the mightiest weapon of destruction devised by the ingenuity of man"

"Education is the most powerful weapon which you can use to change the world"

"Situational variables can exert powerful influences over human behavior, more so that we recognize or acknowledge"

"Welcome those big, sticky, complicated problems. In them are your most powerful opportunities"