Is life an endless circle of joyful depression? A carousel where the horse of life bobs you up for a moment then down again till the inevitable rise back up?
Is it possible for 'the happiest time in your life' to last longer than a week? A set of experiences presented in a particular picture frame, a sale that lasts for seven days only, and then the higher purchase rate of human mortality kicks in.
I have have been perfectly sad, when its so dark no chink of light can breach depressions impregnable walls. But even when bathed in joy and fluorescent radiance there is no perfect happiness as even a single ray of light will cast a shadow...