A-Series and B-Series as Zman and Seder HaZmanim
McTaggart’s series A and series B are two conceptual frameworks proposed by the philosopher J.M.E. McTaggart to analyze the nature of time and its relationship to temporal properties such as past, present, and future.
In McTaggart’s series A, also known as the “A-series” or the “temporal series,” time is understood in terms of the temporal properties of past, present, and future. The A-series categorizes events based on their temporal relations, such as past, present, and future, which are considered essential aspects of events. The A-series views time as a succession of moments where events move from the future, through the present, and into the past. It emphasizes the dynamic and changing nature of time, with events shifting their temporal locations as time progresses. According to McTaggart, the A-series involves the notions of “tensed time,” where events are located in relation to the present moment. The A-series is dynamic and accounts for the changing nature of events over time. It incorporates the common understanding of time as a linear progression from the past through the present and into the future.
On the other hand, McTaggart’s series B, also known as the “B-series” or the “tenseless series,” provides a more static and timeless perspective on time without reference to the subjective experience of time or the concept of temporal becoming. The B-series represents time as an ordered sequence of events without reference to their temporal properties, such as past, present, and future. It presents events as merely existing in a particular order without distinguishing between past, present, or future. In this static framework, events are ordered and related by properties, such as earlier than, later than, or simultaneous with. The B-series views time as a fixed structure where events are arranged in a linear temporal order based only on two criteria—before and after. It eliminates the notion of a moving present moment and treats time as a block-like structure where all events are equally real and existent.
McTaggart argued that both series A and series B are necessary but inadequate to understand the nature of time fully. He contended that the A-series reflects our subjective experience of time with its dynamic and changing nature, while the B-series represents the objective and timeless structure of time. In his view, they are inherently contradictory and cannot fully capture the true nature of time.
In his original work “The Unreality of Time,” McTaggart criticized both the A-series and the B-series as being inherently contradictory and incapable of providing a coherent account of time. He presented what is known as the “tensed theory of time,” which includes both tensed (A-series) and tenseless (B-series) aspects. However, he ultimately concluded that time itself is “unreal” and that our conventional understanding of time, whether in terms of the A-series or B-series, is ultimately flawed.
McTaggart’s analysis of time and the A-series/B-series distinction has sparked significant philosophical debates and has influenced subsequent discussions on the metaphysics of time. It highlights the complex nature of temporal concepts and raises questions about the reality and nature of time itself.
McTaggart’s views on the nature of time have been subject to extensive debate and discussion among philosophers, and his ideas have had a significant impact on the philosophy of time. What is missing from these discussions is the realization that McTaggart’s A-series and B-series closely track the kabbalistic concepts of zman (“time”) and seder hazmanim (“order of the times”).
Zeman (“time”), in Jewish thought, represents time and how it manifests in the physical world (as well as two spiritual worlds above Olam HaAsiyah (the “World of Action,” our physical world)—Olam HaYetzirah (the “World of Formation”) and Olam HaBeriyah (the “World of Creation”). Zeman, in its essence, is viewed as change—the dynamic flow of events from the future into the past, consistent with our intuition for time. While the concept of zman has deep mystical undercurrents and much can be written about it, on this simplistic level, it is almost identical to McTaggart’s A-series.
The more esoteric doctrine of seder hazmanim—the order of the times, in the language of Kabbalah and Chasidut represents seven midot (lower sefirot) of Olam HaAtzilut (the “World of the Emanation”). It is a timeless sequence where there is no past, present, or future. Most importantly, it is a static construct where there is no time flow. In seder hazmanim, one cannot measure the duration of events or time passed from one event to another. The sequence of events is ordered exclusively based on before and after. This is precisely what McTaggart calls the B-series. The concept of seder hazmanim predates McTaggart’s B-series by hundreds of years, if not more. Seder hazmanim are discussed at length by Rabbi Schneur Zalman of Liadi (the Baal HaTanya) in his ma’amarim in the early nineteen century and later expanded in the work of Rebbe Rashab, Samech Vav. However, this concept is rooted in the Lurianic Kabbalah dating back to at least the seventeenth century. This concept is based on the ancient work of Rabbinic Judaism, Midrash Rabba:
Rabbi Yehuda ben Shimon said, “It is not written, ‘Let there be evening’ but rather, ‘And it was evening.’ This teaches us that the order of time (seder zmanim) existed previously.”Midrash Rabba, Ch.3
Whereas Kabbalists and Chassidic masters primarily used the terminology of zman and seder hazmanim, Maimonides and later Jewish philosophers used other names for these two aspects of time: Shiur Zman (“measured time”) corresponding to McTaggart’s A-series, and Dmut Zman (the “essential continuum of time”) or Zman Bilti Meshuar (“Unmeasured Time”) corresponding to B-series (see Maimonides‘ Moreh Nevuchim—The Guide for the Perplexed).
While there is no difference between the “measured time” (shiur zman) found in the works of Jewish philosophers and “time” (zman) found in Kabbalah and Chassidism, there are some nuanced differences between the philosophical notions of “Unmeasured Time” (Zman Bilti Meshuar) and the “essential time” (Dmut Zman) on the one hand, and Kabbalistic “order of times” (seder hazmanim) on the other. Nevertheless, the parallel with McTaggart’s A-series and B-series of time is unmistakable. Let us summarize these parallels in a table:
|Conception of Time||McTaggart’s Metaphysics of Time||Jewish Philosophers’ View of Time||Kabbalistic View of Time used in Hassidism|
|Dynamic time compatible with our intuition of time, where ever-changing moments are ordered according to past, present, and future||A-Series||Shiur Zman (“measured time”) or||Zman (“Time”)|
|Static time, where moments are ordered according to before and after.||B-Series||Dmut Zman (the “essential time”) or Zman Bilti Meshuar (“Unmeasured Time”)||Seder HaZmanim (“Order of the Times”)|
I very much doubt that McTaggart was familiar with Jewish sources discussing the metaphysics of time, let alone the mystical dimension of time, but his famous A-series and B-series track precisely the Kabbalistic concepts of zman and seder hazmanim.
Seeing apparent contradictions between his A-series and B-series, McTaggart got hopelessly confused, which led him to conclude that time is not real. Jewish sources, on the other hand, see seder hazmanim as a proto-time from which time (zman) ultimately emerges. Several medievil and later books of Kabbalah and Hassidism explicitely state that seder hazmanim is the source of the zman (see Pardes of Rabbi Moshe of Cordovero and Avodat HaKodesh of Rabbi Meir Gabbai). Amazingly, the Kabbalah and Chassidic philosophy of Chabad saw time as an emerging property—an idea that came to dominate theoretical physics centuries later.
Contemporary studies of physics and metaphysics of time would be greatly enriched by incorporating classical Jewish sources, particularly found in Kabbalah and Philosophy Chabad, which have much to offer on the subject of time.
 John McTaggart Ellis McTaggart (1866 – 1925)—English philosopher who made a significant contribution to the study of metaphysics of time. A follower of Hegel, he was one of the most prominent British idealist metaphysicians, whose greatest work was The Nature of Existence.
 John M. E. McTaggart, “The Unreality of Time,” Mind, 1908, Vol. 17, pp 457–73; reprinted in J. M. E. McTaggart, The Nature of Existence, Vol. 2, (Cambridge: Cambridge University Press, 1927), Book 5, Chapter 33.
 See my paper, Alexander Poltorak, “On the Nature of Time and the Age of the Universe,” Presented at the International Torah and Science Conference in Miami International University on December 18, 2005. See also my earlier essays, “Five Worlds” (2017), and “Nadab and Abihu — Tragedy in Time,” (2020).
 Rabbi Shneur Zalman of Liadi (founder of Chabad Chassidism, 1745 – 1812) identifies seder hazmanim with the six midot (lower sefirot—Chesed, Gevurah, Tiferet, Netzach, Hod, and Yesod) of the World of Emanation, the Atzilut. (See, for example, Ma’amarei Admur HaZaken, Ki Teitze). For a different interpretation of seder hazmanim, see Haggadah for Passover, with Seder Hazmanim according to Kabbalah, by Rabbi Yaakov of Izhbitza, Lublin, 1910, second edition with additions.
 Rabbi Shalom Dovber, Rebbe Rashab, Yom Tov Shel Rosh HaShanah (Samach Vav).
 Midrash Rabbah on Genesis was probably written between 300 and 500 CE.
 For detail, see the letter of Rabbi Menachem Mendel Schneerson, the Lubabitchter Rebbe, translated into English by my friend, Rabbi Tzvi Freeman, published in B’Ohr HaTorah and available online at https://www.chabad.org/therebbe/letters/default_cdo/aid/74601/jewish/A-Letter-on-Time.htm#footnoteRef8a74601.