When the moment of difficulty arises and oppresses the mind, then wisdom is not visible, like darkness when the sun rises.

The inversion of the classic metaphor is revealing. Usually it is said that wisdom dissipates darkness like the sun; here, difficulty is the sun that dissipates wisdom. Kaṣṭa-kāla — the critical moment — is not duration but intensity: an instant of devastating news, betrayal, loss, can obscure years of study. Pīḍā is physical and mental pressure simultaneously; it compresses, reduces, crushes. Prajñā does not disappear — it remains there, latent — but ceases to be visible, operative, accessible. The seeker in crisis does not need more theory; they need a method for wisdom to resurface under pressure. This is what the Stoics called premeditatio malorum and what yoga calls tapas: deliberate preparation for the moment when the mind fails. It is not pessimism, it is training. Darkness is not permanent, but neither is the sun of clarity without practice.