Yesterday gets in the way of tomorrow. Well, it can. Ideas and beliefs are generated and agreed upon. In our minds (individually and collectively) stories get attached to these. Identity is formed. Culture.
These are the things that weigh on us as we try to understand what is next. They hold us to the ground like cement boots. Yesterday is over. Today is here and all of what we came to know as true then may prove to be completely wrong.
Real freedom is to let this go. Let go of yesterday. Rather, integrate it. Then let it go.