A. B.

“Everything on earth is in a state of constant flux. Nothing keeps the same, fixed shape, and our affections, which are attached to external things, like them necessarily pass away and change. Always beyond or behind us, they remind us of the past which is no longer or anticipate the future which is often not to be: there is nothing solid in them for the heart to become attached to. Thus the pleasures that we enjoy in this world is almost always transitory; I suspect it is impossible to find any lasting happiness at all. Hardly is there a single moment even in our keenest pleasures when our heart can truly say to us: 'if only this moment would last for ever', and how is it possible to give the name happiness to a fleeting state which still leaves our heart anxious and empty, and which makes us regret something beforehand or long for something afterwards?

But if there is a state where the soul can find a position solid enough to allow it to remain there entirely and gather together its whole being, without needing to recall the past or encroach upon the future, where time is nothing to it, where the present lasts for ever, albeit imperceptibly and giving no sign of its passing, with no other feeling of deprivation or enjoyment, pleasure or pain, desire or fear than simply that of our existence, a feeling that completely fills our soul; as long as this state lasts, the person who is in it can call himself happy, not with an imperfect, poor, and relative happiness, such as one finds in the pleasures of life, but with a sufficient, perfect, and full happiness, which leaves in the soul no void needing to be filled.
The feeling of existence stripped of all other affections is in itself a precious feeling of contentment and peace which alone would be enough to make this existence prized and cherished by anyone who could banish all the sensual and earthly impressions which constantly distract us from it and upset the joy of it in this world.”
― Jean-Jacques Rousseau, Reveries of the Solitary Walker