良心

1. Origins, structure, and basic meaning

• Structure: Written 良心 and read りょうしん, it is an inner moral sense that judges right and wrong and guides conduct.
• Basic usage: It troubles someone tempted to keep a found item and leads another to refuse wrongdoing.

2. Common pitfalls and similar expressions

• Inner judgment rather than external rule
  • It motivates action through personal moral awareness, even apart from law or instruction.