1. "The gem cannot be polished without friction, nor man perfected without trials." - Confucius

2. "In the middle of difficulty lies opportunity." - Albert Einstein

3. "The only way out is through." - Robert Frost

4. "Tough times never last, but tough people do." - Robert H. Schuller

5. "The greatest glory in living lies not in never falling, but in rising every time we fall." - Nelson Mandela

6. "When you come out of the storm, you won’t be the same person who walked in. That’s what the storm is all about." - Haruki Murakami

7. "Difficulties strengthen the mind, as labor does the body." - Seneca

8. "Life is not easy for any of us. But what of that? We must have perseverance and above all confidence in ourselves." - Marie Curie

9. "Adversity introduces a man to himself." - Albert Einstein

10. "The oak fought the wind and was broken, the willow bent when it must and survived." - Robert Jordan

11. "Every adversity carries with it the seed of an equal or greater benefit." - Napoleon Hill

12. "The greater the difficulty, the more glory in surmounting it." - Epicurus

13. "Life’s challenges are not supposed to paralyze you; they’re supposed to help you discover who you are." - Bernice Johnson Reagon

14. "The gem cannot be polished without friction, nor man perfected without trials." - Chinese Proverb

15. "It is during our darkest moments that we must focus to see the light." - Aristotle