For us limited bipeds, everything that we call real, unbeknownst to us, is a composition of a mysterious extra-physical reality or the same, a positive essence, but one totally unconditioned which lies beyond our sensory nets, so to speak.
According to the Buddha, composed things, which are dependent arisings of this extra-physical reality, are not real. Chasing after them is spiritually unsatisfactory and leads to rebirth and still more dissatisfaction.
In order to be free from the dissatisfaction of chasing after things which are not ultimately real we have to gain access to the extra-physical reality which alone is real. Unfortunately, owing to our ignorance, we have no access to it.
Buddhism is very good at advertising that it has the necessary tools which allow us to see this extra-physical reality from which all things are composed. But as for the use of these tools, I am inclined to believe that we first need to have the correct overview of Buddhism (and that includes Zen).
If someone were to ask me what is the correct overview, one that is simple to understand, I would tell them that the difference between a vital functional being and a being that is dead, is life, life being the animative principle of force that animates us. And while as living beings we show the effects of life active within us, we are far from meeting it face to face.
If we get the overview down, correctly, then the tools will be used in a specific way to help us meet, face to face, life and with it experience direct communion with the extra-physical reality from which all things are composed. Said again, all these tools such as dhyana will help us to uncover life which I hasten to add is undying and who we really are.