5 ideas
That period is dense with firsts: first love, first job, leaving home, forming an identity. Novelty and identity formation stamp those events deeply and make them anchors of the life story, so early adulthood fills the album.
We judge how long a past stretch of time lasted by how many distinct, retrievable events it holds. In youth, frequent novel experiences leave many markers, so the years feel long in retrospect. As life settles into routine, the same span yields few distinctive memories and seems to have passed quickly, which is why time appears to accelerate with age.
People systematically misdate past events, most often placing them more recently than they actually happened (forward telescoping). A vivid, easily retrieved memory feels near, and we read that vividness as recency. This distortion helps explain the common shock at learning how long ago something occurred.
In Israel in 1988, John Demjanjuk was convicted and sentenced to death as 'Ivan the Terrible' of Treblinka, largely because several survivors identified him with complete confidence from photographs decades after the war. In 1993 the Israeli Supreme Court overturned the conviction after Soviet archival evidence pointed to a different man, Ivan Marchenko. The case shows that memories of traumatic events can be sincere, vivid and emotionally certain and still wrong in their details.
Déjà vu occurs when the brain's feeling of familiarity fires for a present situation while no actual memory can be retrieved to explain it. The result is an uncanny sense of having lived this moment before.