The dictionary says:
subha : [adj.] lucky; auspicious; pleasant. (Lal says: useful or beneficial)
sukha : [nt.] happiness; comfort.
The meanings are pretty similar. Why the additional term (a)subha instead of just “tilakkhana” (anicca, dukkha, anatta)?
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The Sotapanna has no vipallasa about anicca and anatta. Does it mean, the Sotapanna has full knowledge or panna about anicca/anatta?