Shloka 13
च्यवन-कुशिक-संवादः
Cyavana–Kuśika Dialogue on Hospitality, Service, and Lineage Questions
भीष्म उवाच रेतजो वा भवेत् पुत्रस्त्यक्तो वा क्षेत्रजो भवेत् अध्यूढ: समयं भिनत्त्वेत्येतददेव निबोध मे
bhīṣma uvāca | retajo vā bhavet putras tyakto vā kṣetrajo bhavet | adhyūḍhaḥ samayaṃ bhinattv ity etad eva nibodha me ||
ビーシュマは言った。「王よ、自らの種より生まれた子は、まさしく己の子である。だが『田より生まれし子』（クシェートラジャ）—後嗣のために他の男を立て、妻の胎に宿して生まれた子—も、その授種者が己の権利を捨てたなら、夫の子となる。『アディユーダ子』（adhyūḍha）についても同じ理を知れ。先の取り決め（サマヤ）を破る、あるいは退けるなら、名分は移り変わる。要するに、父としての権利は血の種だけで定まるのではなく、承認された同意、権利放棄、そして社会の約定によって定まるのだ。」
भीष्म उवाच
Educational Q&A
The verse teaches that sonship (and the attendant rights/duties) is determined by dharmic recognition and agreement: a biological son is straightforwardly one’s own, but in kṣetraja/adhyūḍha cases the decisive factor is whether the begetter renounces his claim and whether the governing agreement (samaya) is upheld or breached.
Bhishma is instructing the king on dharma concerning categories of sons and the legitimacy of lineage. He clarifies how retaja, kṣetraja, and adhyūḍha sons are to be regarded, emphasizing the role of consent, renunciation, and social/legal convention.