प्रदीपिकोऽग्निना वध्यः ॥ कZ_०२.३६.२५ ॥
pradīpiko 'gninā vadhyaḥ
தீ வைத்தவன் (தீவைத்துத் தீங்கு விளைவிப்பவன்) தீயால் மரணதண்டனைக்கு உரியவன்।
To create maximum deterrence for a high-externality crime that can destroy dense urban property, granaries, and lives; the punishment mirrors the harm (lex talionis-style proportionality).
Primarily public-order: arson threatens collective security and state assets, justifying the severest penalty.