"Happiness, true happiness, is an inner quality. It is a state of mind. If your mind is at peace, you are happy. If your mind is at peace, but you have nothing else, you can be happy. If you have everything the world can give - pleasure, possessions, power - but lack peace of mind, you can never be happy."
- Dada Vaswani

"The most dramatic conflicts are perhaps, those that take place not between men but between a man and himself -- where the arena of conflict is a solitary mind."
- Clark Moustakas

"It is the mind’s job to protect and take care of you, to solve your problems and make sure you’re safe. So, if you feel a surge of emotional upset, it moves into action, trying to help, looking for the source of the upset—for the problems—and generating solutions."
- Unknown

"The greatest discovery of my generation is that human beings can alter their lives by altering their attitudes of mind." 
- William James

"There is no separation of mind and emotions; emotions, thinking, and learning are all linked."
— Eric Jensen

"As long as you don't forgive, who and whatever it is will occupy a rent-free space in your mind."
- Isabelle Holland

"Strength is a matter of a made up mind."
- John Beecher

"To be capable of steady friendship or lasting love, are the two greatest proofs, not only of goodness of heart, but of strength of mind."
- William Hazlitt

"There is no limit to what you can imagine. And with commitment, with effort, what you can imagine you can become. Put your mind to work for you. Believe that you can do it. The world will tell you that you can't. Yet, in your belief you'll find the strength, you'll find the ability, to do it anyway."
- Ralph Marston

“You have power over your mind - not outside events. Realize this, and you will find strength.”
― Marcus Aurelius, Meditations

"The good Lord gave you a body that can stand most anything. It’s your mind you have to convince."
- Vince Lombardi

"It is a man’s own mind, not his enemy or foe, that lures him to evil ways."
- Buddha

"You can conquer almost any fear if you will only make up your mind to do so. For remember, fear doesn't exist anywhere except in the mind."
- Dale Carnegie

Not all issues will be a "cloud in the horizon"....
"Maturity of the mind is the capacity to endure uncertainty."
- John Finley

"Mental toughness is many things and rather difficult to explain. Its qualities are sacrifice and self-denial. Also, most importantly, it is combined with a perfectly disciplined will that refuses to give in. It’s a state of mind – you could call it character in action."
- Vince Lombardi

"The good Lord gave you a body that can stand most anything. It's your mind you have to convince."
- Vince Lombardi

https://www.flickr.com/#/photos/lessonsproject/14852697958/

"Many people think that if they were only in some other place, or had some other job, they would be happy. Well that is doubtful. So get as much happiness out of what you are doing as you can and don't put off being happy until some future date."
- Dale Carnegie

"No man is happy who does not think himself so."
- Publilus Syrus

"Most people are as happy as they make up their minds to be."
- Abraham Lincoln