Canto 2 -
Ayodhyā-kāṇḍa
Chapter 8: The Conversation Between Kaikeyī and Mantharā
Text 2.8.21
अनर्थदर्शिनी मौर्ख्यान्नात्मानमवबुध्यसे।
शोकव्यसनविस्तीर्णे मज्जन्ती दुःखसागरे॥
anartha-darśinī maurkhyān nātmānam avabudhyase
śoka-vyasana-vistīrṇe majjantī duḥkha-sāgare
anartha-darśinī = you see calamities as prosperity; maurkhyāt = due to foolishness; na = not; ātmānam = that you; avabudhyase = you do understand; śoka-vyasana-vistīrṇe = that is extensive with calamity and sorrow that causes lamentation; majjantī = are sinking; duḥkha-sāgare = in an ocean of misery.
Due to your foolishness, you see calamities as prosperity. You do not understand that you are sinking in an ocean of misery that is extensive with calamity and sorrow that causes lamentation.
Anartha-darśinī can also mean artha-adarśinī indicating that Mantharā thought that Kaikeyī is not experienced in understanding what is required due to her foolishness, that is, lack of due deliberation.
Mantharā thinks that Kaikeyī would experience sorrow, that is, misery born of separation from her dear Bharata for Rāma would deprive Bharata of the kingdom and exile Him to the forest. She also considers that this will lead to Kaikeyī’s calamity because she would become unhappy in an ocean of misery in the form of service to her co-wives.