Happiness

Was watching CNN this morning and there was a report about happiness and what it takes to make some people happy. Start thinking about the subject, for the first time I don’t have an answer to a question or am as confused as I started.

Is it true that no one can make you happy except you? Can your environment influence your happiness or can your happiness influence your environment?
Is it possible to be at peace with yourself but not happy? What is happiness? Can you be happy without be content with what you have?
Can happiness be measured?

Thinking hard and scratching my head looking for answers.