On Rosh Hashanah, we sublimate the previous year.
In other words, you can never forget without remembering.
I need to relive and review the past year, so I can elevate it until it appears to have disappeared.
This process of elevation, or sublimation, cannot occur unless we first recall faded memories.
Thus, forgetting implies recollection.
–Rabbi Adin Steinsaltz
From The Seven Lights by Rabbi Adin Steinsaltz