was unable to put into words the impact he felt. Sekine knew he now faced a different issue, yet his interest continued to centre on topological space. Lee Ufan shed a light on the ‘accident’ that struck Sekine, Koshimizu and Yoshida :Phase-Mother Earth is considered to be the initial work of the Mono-ha movement. It was later credited as the "big bang" of the movement. The work was re-created in 1970 for the Osaka World Expo, in 2008 and again in 2012 for the exhibition Requiem for the Sun: The Art of Mono-ha, Blum and Poe, Los Angeles. Other Important Works Phase—Sponge (1968) (位相：スポンジ) was a white cylinder of sponge, distorted under the weight of a black sheet of iron laid on top of it. One can understand from this work that structure remains the same even if there are changes in form, and that what is deformed can be restored to its original shape. Writing about this work, Lee Ufan suggested that “perhaps all primitive people had to do was to stack up rocks like dolmens. However, in today’s industrial society, an iron plate on a sponge cylinder more naturally elicits a response”. At Sekine’s first solo exhibition at Tokyo Gallery in 1969, he exhibited Phase of Nothingness—Oil Clay (1969) (空相—油土), which consisted of a huge mass of oil clay exhibited in its natural state. Viewers were allowed to touch this work and reshape it, implying that sculpted or not, and in contrast to its dominant physical presence, this “sculpture” was transient. Of this piece, curator Simon Groom wrote: Phase of Nothingness—Water (1969) (空相：水) consisted of two containers of water, one a 110 cm high cylinder and the other a 30 cm high rectangular box. The containers were painted black so that the water would appear invisible, but as viewers were allowed to touch the work, once they did so, ripples made the presence of the water known. Phase Of Nothingness / Venice Biennale In July 1970, along with Shusaku Arakawa, Sekine was chosen to exhibit at the Japan Pavilion at the Venice Biennale. He contributed Phase of Nothingness (空相), which consisted of a large stone placed on top of a tall square column of mirrored stainless steel. The column reflects the surrounding scenery and almost disappears from view, while the stone appears to float in the air. Yoshiaki Tono, commissioner of the Japan Pavilion wrote : Yoshiaki Tono