These words are from Happiness: A Guide to Developing Life’s Most Important Skill by Matthieu Ricard and translated by Jesse Browner. I really enjoy this book, and would encourage you to read it. This quote is about the difference between genuine happiness and what we often think of as means of achieving it.
Once at an open meeting in Hong Kong, a young man rose from the audience to ask me: “Can you give me one reason why I should go on living?” This book is a humble response to that question, for happiness is above all a love of life. To have lost all reason for living is to open up an abyss of suffering. As influential as external conditions may be, suffering, like well-being, is essentially an inner state. Understanding that is the key prerequisite to a life worth living. What mental conditions will sap our joie de vivre, and which will nourish it.
Changing the way we see the world does not imply naive optimism or some artificial euphoria designed to counter-balance adversity. So long as we are slaves to the dissatisfaction and frustrations that arise from the confusion that rules our minds, it will be just as futile to tell ourselves ‘I’m happy! I’m happy!’ over and over again as it would be to repaint the walls of ruins. The search for happiness is not about looking at life through rose-colored glasses or blinding oneself to the pain and imperfections of the world. Nor is happiness a state of exaltation to be perpetuated at all costs; it is the purging of mental toxins, such as hatred and obsession, that literally poison the mind. It is also about learning how to put things in perspective and reduce the gap between appearances and reality. To that end we must acquire a better knowledge of how the mind works and a more accurate insight into the nature of things, for in its deepest sense, suffering is intimately linked to a misapprehension of the nature of reality.