With the intent to provide some order in the plethora of phenomenological studies, the philosopher Joseph Kockelmans distinguished three broad streams of phenomenological publications: foundational, exegetical, and phenomenal streams. The foundational kinds of writings and publications establish the nature, conditions, and assumptions of phenomenology. The exegetical kinds of phenomenological writings and publications explore the ways that phenomenological perspectives, principles, and starting points may speak to the varieties of phenomenological concepts, themes, topics, theories, and interests that are addressed in the literature. And the phenomenal kinds of writings and publications distinguish themselves by actually doing or practicing the method of phenomenology on concrete phenomena and everyday events. In Kockelmans’ view, and he cites Spiegelberg (1975), it is doing phenomenology, rather than mostly theorizing about it, that is needed.
Edmund Husserl, Martin Heidegger, Edith Stein, Jean-Paul Sartre, and Maurice Merleau-Ponty are probably among the best-known originators of the movement of phenomenology. The foundational structures of these writings offer fundamental insights that are inexhaustible in their philosophical significance for those seriously interested in understanding phenomenology.
Husserl and Heidegger are the highly gifted thinkers who took their leads from the works by Aristotle, Nietzsche, Brentano, Hegel, and others. Husserl’s foundational works (1970, 1983) gave us the method of the reduction that must establish the phenomenological attitude; the mode of intentionality of consciousness that allows the things of the world to give themselves as phenomena; the epoché that involves the suspension of the natural attitude in favor of the transcendental reduction, the lifeworld as the source of our lived experiences, and the means of bracketing to assist in identifying eidetic aspects of phenomena. Heidegger’s works (1962, 1977, 1982, 2001) gave us the focus on the Being of being; human ontology as Dasein; the characterization of the phenomenological method as to let that which shows itself be seen from itself in the very way in which it shows itself from itself; his notions of zuhanden and vorhanden; and his writings on technology whereby technology is not to be understood instrumentally but as the explication of the general comportment by which technology may shape our existential ways of being.
Following them there are other early and subsequent phenomenological publications that offer founding phenomenological ideas. The significance of this first stream of publications is that they are foundational to the development and understanding of the philosophical project of phenomenology itself.
Exegetics is the critical discourse or philosophical commentary, explanation, or argumentative interpretation of a text. Exegetical publications are the second stream of phenomenological literature. This stream of phenomenological texts tend to take up in a critical, and philosophical manner the arguments and positions of the founding authors mentioned above as well as address theoretical issues of more exegetical philosophers and scholars of phenomenology. This literature is enormously variegated and extensive, sometimes offering interesting comparative studies and probing thought-provoking topics, other times texts that are steeped in “language” and only of interest and readable by specialized philosophers, and there are publications that are engaged in energetic hair-splitting, cleverly raising fault-finding objections, and serving academic exegetical arguments. The exegetical structures of these enormously diverse and numerous texts unfortunately may be seen to include an almost interminable array of historical, theoretical, and liberal topics that are sometimes tedious, pretentious, intellectualist, and captious..
The phenomenal stream of phenomenological publications features studies that return to and start out from experience. This third stream neither primarily establishes phenomenological foundations, nor primarily addresses theoretical topics, arguments, and contestations. Instead, the phenomenal stream of phenomenological publications is composed of texts that aim to “practise” or “do” phenomenology on concrete experiential topics of the lifeworld. Authors of the phenomenal stream try to do, as Kockelmans says, what was described as possible and necessary in the foundational, theoretical, and exegetical writings of phenomenologists. They “do” what the works of the founding originators and brilliant exegetical scholars and academic commentators suggest or imply are the possible, original, and necessary task of phenomenology: to explicate the phenomenality of phenomena as they give themselves in and as human consciousness and experience. So, this stream of publications includes phenomenological works that address topics that are primarily concrete and relevant to the experiential lives of clinical professional practitioners as well as the experiential concerns of everyday lives. It is inherent in the original conception and practice of phenomenology that it minimizes or even avoids the role of theory and abstraction in doing phenomenological description and research