Thinking about achieve our targets we think about a straight way. When we think about learning we also think about a straight way.
Circle line in London's Underground can demonstrate you that, although physically, you can leave the train in the same station that you took before, in your life you will be, sure, in another place.
People you meet during the travel will transform you to deep inside so you never will be the same person. And you will find those changes through memory. We live only in the past beacause of memory. Memories that hammered our soul and printed on it their fingerprints ocurred years ago, and memories recorded 1 second ago that because of the computational delay of our brain we think that we are living the present.
Although you are living at present your conscience always lives in the past, so:
Present is a "Quimera", future doesn't exists and past are our memories...