Happiness is not the cause of gratitude...it is the result.
2 Quotes on Gratitude by Ralph Marston:
“Make it a habit to tell people thank you. To express your appreciation, sincerely and without the expectation of anything in return. Truly appreciate those around you, and you'll soon find many others around you. Truly appreciate life, and you'll find that you have more of it.”
“What if you gave someone a gift, and they neglected to thank you for it - would you be likely to give them another? Life is the same way. In order to attract more of the blessings that life has to offer, you must truly appreciate what you already have.”