Solitude is painful when one is young, but delightful when one is more mature. - Albert Einstein. [알버트 아인슈타인] on February 27, 2025 Albert Einstein Evolution Inner peace Introspection Life experience Life stages Maturity Perception change Personal growth self-awareness Self-Discovery Self-reflection Solitude wisdom Youth 고독 내면성찰 성숙 알버트 아인슈타인 진화 +