"I have discovered that every moment you devote to thinking about someone who has wronged you is a minute you have stolen from a much worthier pursuit: attracting those people who will help you."

"You are here to enrich the world and you impoverish yourself if you forget the errand." -- Woodrow Wilson

"Every second you dwell on your past, you steal from your future. Every minute you spend focusing on your problems, you take away from finding your solutions."

"Let us be kinder to one another." -- Aldous Huxley

"Be the change that you wish to see most in your world." -- Gandhi

These are all quotes taken from a book I recently made a thread about (the one on perspective). The author is Robin Sharma, the book is Who Will Cry When You Die? and it is full of gems like these. The ones that don't have a name after them are Robin Sharma's words.