American Quotes and aphorisms about irreversible Gary Larson ,, Humans have changed ecosystems more rapidly and extensively than in any comparable period of time i... Barbara Jordan Valerie Jarrett Dan Quayle Jason Epstein Vinod Khosla Sean M. Carroll ,, The particular aspect of time that I'm interested in is the arrow of time: the fact that the past i... Thomas P. O'Neill Richard Phillips Andrew Jackson