Kokoro, by Natsume Soseki (paragraph #536)

「さう六づかしく考へれば、誰だつて確かなものはないでせう」

translation

"If you think about it like that, no one can be sure."

kanji (pronunciations & definitions)
: six (む), six (むう), six (ろく), 6, 6 : thought (こう), report on one’s investigation into …, deceased father : who (た), who (たれ), who (だあれ), who (だれ) : sure (たしか), certain, positive, definite, reliable

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