“I've learned from experience that the greater part of our happiness or misery depends on our dispositions and not on our circumstances.”

“Success comes when people act together; failure tends to happen alone.”

“The greatest deception men suffer is from their own opinions.”

“There’s about as much educational benefit studying dolphins in captivity as there would be studying mankind by only observing prisoners held in solitary.”

“They must often change, who would be constant in happiness or wisdom.”

“Change your thoughts and you change your world.”