In 1954, Zao Wou-Ki set aside narrative paintings of still lifes, animals, and landscapes. The poetic spaces and expressive elements of his previous paintings evolved into spiritual, mystical forms. This was the beginning of his Oracle Bone Period. Figurative depictions disappeared completely, replaced by symbols that resembled characters but could not be pronounced or understood. In his own words: “My paintings became indecipherable. Still lifes and flower petals no longer existed as I moved toward an imaginary, unidentifiable form of writing.” In traditional Chinese aesthetics, painting and calligraphy were considered a unified field: two interrelated genres that possessed a unique capacity to fascinate. In contrast, in the West, painting and calligraphy are separate disciplines. During his Oracle Bone Period, Zao Wou-Ki subverted the pre-existing separation between these categories of art in the West, combining painting with primeval characters that resembled ancient oracle bone inscriptions. Spirits (Lot 1058), like sunlight shimmering on rippling blue water, creates effects completely different from the dense and rich qualities of oil paints, demonstrating how the artist skilfully exploits the potential of each medium and infuses each painting with extraordinary knowledge and deft technique.

1954年，趙無極放下敘事性風格，朝著抽象的方向急速啟程。過往畫面中的詩性空間，連同表象的元素，進一步幻化成神秘的形體，由是揭開「甲骨文時期」之序。具象的描寫完全消失，取而代之的是宛如文字卻不能言喻的符號，正如其自敍：「我的畫變得無法解讀，靜物和花朵不再存在，我走向一種想像的，難以辯識的書寫。」中國傳統美學強調「書畫合一」，而在西方，繪畫與書寫則是截然不同的觀念。趙無極在甲骨文時期所創的作品，打破西方固有的藝術形式，在畫作上呈現彷如古拙的甲骨文，寫字、寫畫從此同化。象形文字本是取自自然的造形符碼，趙無極的甲骨文作品復元漢字的繪畫本質，一筆一劃串成金石碑文，透露著超然於文本的象徵意義。甲骨文時期的油畫作品多以深邃的單色調為主，水彩較為明澈透亮的特質讓趙無極能夠增加用色，《士氣》 （拍品編號1058）中湖藍、紫和金黃的組合，如陽光映射下的透靈碧水，為畫作注入非一般的通透力和渲染力。