What Chekhov captures here is the peculiar ontological sleight of hand we perform with memory—the past doesn't merely disappear; it becomes *nothing*, a void that contradicts our sense of having lived at all. Most of us think of time as a fixed quantity we've accumulated, but he's suggesting something stranger: that yesterday possesses no duration, no substance, no reality *now*. When you finish a thirty-year career and retire, those three decades you supposedly "spent" vanish into a kind of temporal nonexistence, leaving you with only the thin present moment. The quote matters because it redirects our anxiety from squandering time to the deeper vertigo of existence itself—the fact that living is perpetually erasing what we've just done, making us simultaneously full of history and utterly unmoored.