Reflections on the Japanese concept of sora 空 (void)
Here, I share some etymological connections I stumbled upon when engaging with the Japanese concept of sora (空). There are some interesting links to Daoism, the least action principle, meditation, and nothingness.
Sora (wiktionary) is one of the two Japanese pronunciations of the Chinese character 空 which is used in Japanese as well. Its meaning is often described as “void”. The alternative Japanese pronunciation of the character is kū. The Chinese pronunciation of the same character is kōng. Interestingly, in Japanese, the meaning of 空 lies somewhere between “nothing” and “heaven”. In Chinese, it is typically used as “sky” or as “empty” whereas 天 (tiān) means “heaven” and 無 (wú) means “nothing”. This wú is the same wú as in wúwéi (無爲) i.e. action through non-action, or as one might alternatively say: effect in the absence of force. So here “absence” = wú = 無 ~ 空 = kōng = kū = sora. Also note Edward Slingerland’s brilliant book on 無爲 .
There is also a direct connection to the dao (道) of Daoism: 空道 = kōngdào [Chinese] = kūdō [Japanese] = “way of the sky” or “way of the void” — perhaps one could even say “way of least resistance”. Another remarkable connection is to the ancient Sanskrit word śūnya (wiktionary), which is the root of sora. Śūnya in turn is also the root for Arabic ṣifr which is the root for Latin zephir. Zephir in turn is the root for English zero. In other words, the Japanese sora and the English zero have the same Sanskrit root — they are remote cousins in a sense. In Sanskrit, śūnya means “void” and śūnyatā means “voidness”. Śūnyatā is the state that is also associated with meditation i.e. being in a state of voidness. Now, apparently śūnyatā is closely related to anattā, which is the Buddhist concept of non-self, or in simpler terms: of overcoming one’s ego.
There are also conceptual ties to branches of Western philosophy. German philosopher Martin Heidegger developed the notion of das Nichts (the Nothingness) as a central concept of his philosophy. Das Nichts appears to coincide with the notion of 無 and 空 — as discussed in [2-4]. This is perhaps unsurprising given that Heidegger has been described as the Western philosopher closest to Daoism and Zen Buddhism (“Heidegger is the only Western philosopher who not only thoroughly intellectually understands but has intuitively grasped Taoist thought” Chang Chung-yuan , quoted in May 1996 ). Heidegger uses as a metaphor for das Nichts, the so-called Lichtung. Lichtung has been translated as a clearing or a lighting in a forest. The clearing is a void but it is not nothing, it still is something. And it is in the clearing where unconcealment (Unverborgenheit) occurs, which Heidegger often refers to via the Greek term aletheia (ἀλήθεια) as a signifier to the concept of disclosure of a truth.
I am not a trained linguist — but as a lay person, I can only marvel at the various etymological and philosophical interconnections between words and concepts across the Eurasian continent, including Japan and China, the Indian subcontinent, the Middle East, and Europe.
 Slingerland, E. (2014). Trying not to try: The ancient art of effortlessness and the surprising power of spontaneity. Canongate Books.
 Nelson, E. S. (2012). Demystifying Experience. Angelaki, 17(3), 65–74. https://doi.org/10.1080/0969725X.2012.722396
 Krummel, J. W. M. (2018). On (the) nothing: Heidegger and Nishida. Continental Philosophy Review, 51(2), 239–268. https://doi.org/10.1007/s11007-017-9419-3
 Wohlfart, G., & Heitz, M. (2003). Heidegger and Laozi: Wu (Nothing)—on chapter 11 of the Daodejing. Journal of Chinese Philosophy, 30(1), 39–59. https://doi.org/10.1111/1540-6253.00105
 King, R. E. (2017). The clearing of being: A phenomenological study of openness in psychotherapy [PhD Thesis]. Middlesex University.
 May, R. (1996). Heidegger’s hidden sources: East Asian influences on his work. Psychology Press.
 Ma, L., & van Brakel, J. (2006). Heidegger’s Comportment toward East-West Dialogue. Philosophy East and West, 56(4), 519–566.
 Chang, Chung-yuan. 1975. Tao: A New Way of Thinking: A Translation of the Tao T& Ching with an Introduction and Commentaries. Taibei: Dun Huang