Passion for living, learning, passion in itself, a necessity of life, for without passion what are we, but processes and algorithms that procure nothing, think nothing, create nothing, and feel nothing. Life is a product of evolution, but passion is a product of life, poured through emotion, and tempered with time.
We all must be passionate. Even if we fight it, seclude ourselves from it, hide away, and run from its tendrils and vices. Life without passion is sterile and clean of all the dirt that colors our endeavors, and dreams.
So, you do what you love wondering if you love what you do. Either you must catch up with life, or live with the knowledge that you never will.