The Ancient Elders explained: As one repeats the observation and contemplation of the unavoidable dissolution of all phenomena by their decay, gradual destruction, fall, breakup and ultimate ceasing, then all formations, all constructions, all kinds of becoming, generation, birth, life, destiny, station, or abode, appears as a great dread of total terror!!! When one sees how past phenomena have ceased, present ones are ceasing, and those to be generated in any far future all inevitably also will cease, then what is called -knowledge of appearance as terror- arises in the meditating disciple just in the same way a mother gives up of all hope, when she see her 3 sons beheaded one after the other... When seeing the 2nd son axed she knows: All 3 will die... !!! The meditator's seeing & noting the ceasing of all past, & all present phenomena, is like the woman's seeing the eldest & the middle son's head being slashed off... His realizing the unavoidable ceasing of all future phenomena, by comprehending: All phenomena, whether mental or material, arising in any future will all cease too! is like her giving up hope for the youngest son, thinking: He too will die like them... Vism 645