noun, noun which may take the genitive case particle 'no'
self-deception
A yojijukugo meaning the act of deceiving oneself, often used in psychological or philosophical contexts.
彼の楽観は自己欺瞞に過ぎない。
His optimism is nothing more than self-deception.
自己欺瞞に陥らず、現実を直視すべきだ。
You should face reality without falling into self-deception.
自己暗示 is autosuggestion, often used in a neutral or therapeutic sense, while 自己欺瞞 implies a negative, self-deceptive act.
A yojijukugo composed of 自己 (self) and 欺瞞 (deception). The exact historical origin is uncertain, but it follows the typical pattern of Sino-Japanese four-character compounds.