Who said "I must remain calm and methodical in all endeavors."?

This quote is attributed to Dexter.

I must remain calm and methodical in all endeavors. - Dexter

"I must remain calm and methodical in all endeavors."

Dexter Patience

"What does this button do?"

"I must focus on my work."

"Science rules!"

"Dee Dee, get out of my laboratory!"

"Patience is a virtue I'm still learning."

"I may be a redhead, but I'm not a hothead."

"Patience is a virtue."

"Patience is a virtue I never learned."