恒こう真しん式しき

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Meanings

1

noun

logic

In logic, a proposition that is always true regardless of the truth values of its components.

constancy, always

真true, reality, Buddhist sect

式style, ceremony, rite

恒こう偽ぎ式しき
恒偽式 is a contradiction (always false), while 恒真式 is always true.
トートロジー
トートロジー is the loanword equivalent, often used in both logical and rhetorical contexts.

Compound of 恒 (constant) + 真 (true) + 式 (formula). The term is a direct translation of the English 'tautology' in a logical context.