belong to the anti-art trend (Yamanote Line Incident, and other events of the group Hi-Red Center, which he co-founded). Sekine’s early work reflected this approach. He was included in the seminal Tricks and Vision: Stolen Eyes group exhibition held at Tokyo Gallery and Muramatsu Gallery in 1968. There, he exhibited Phase No.4 (1968) (位相 No.4), a wall-mounted sculpture. Depending on the angle from which one viewed this work, its cylindrical shape appeared whole or fragmented. Sekine held his first solo exhibition at Tokyo Gallery the following year. Phase—Mother Earth The major turning point in Sekine’s career came in October 1968, when he created the work Phase: Mother Earth in Kobe’s Suma Rikyu Park for the First Open Air Contemporary Sculpture Exhibition (第一回野外彫刻展). Made with the assistance of Susumu Koshimizu and Katsuro Yoshida, the work consisted of a hole dug into the ground, 2.7 meters deep and 2.2 meters in diameter, with the excavated earth compacted into a cylinder of exactly the same dimensions. He conceived the work as a “thought experiment” that would deal with the laws of awareness of phases of space—a form of “reasoned thought that deduces whether or not one’s hypotheses are true, and in some cases, can ignore the physical phenomena of reality.” He further elaborated : "If you dig a hole in the earth and keep digging forever, eventually the earth will be like an eggshell, and if you go on to pull out all the earth, it will be reversed into a negative version of itself. " Despite the simple structure, the act of trying to compact the earth into the desired shape proved technically challenging. Eventually, Sekine consulted a geology laboratory at the University of Tokyo, which advised him to alternate layers of earth with cement, before treading them down firmly. At the time, Sekine knew virtually nothing about Land Art. Creating a work outdoors was not even his own idea; he merely happened to be invited to participate in an outdoor sculpture exhibition. When Sekine finished the work, however, something unexpected happened: he was simply stunned by the sheer power of the ‘thing’ (mono) before him. The reality of it overwhelmed whatever concepts he originally had in mind. Sekine recently likened it to an ‘accident’ that hit him (and the two other Mono-ha artists who assisted him, Yoshida and Koshimizu Susumu) over the course of a week, though at the time he