Whether you know anything else or not, you do know that you exist. It means there is a self and it is only a question of realising it. Can anyone climb Mount Everest? Definitely not, because not everybody has the capacity to do that. But all of us have a self, and realising it is an inward process, so it is definitely possible.
What you can do on the outside depends on many things. When it comes to what is within you, it is just a question of your willingness. If you are interested in living your life with full depth and dimension, how can you live without self-realisation? If you are interested in experiencing all the possibilities you carry within yourself, how can you explore them without self-realisation? Self-realisation is not an abstract dimension that is not relevant to people. Every human being should strive for it because the more you realise yourself, the better you live.
When we say self-realisation, we are not talking about understanding your physiology or your psychology alone, we are talking about understanding the very fundamentals of who you are. When you stand here, you look at yourself as a person, but how did this person happen? This body, when it was born, it was so small. Now it has become so big ^ how? Was it created from inside or from outside? Definitely from inside. So that which creates this body is within you; the very source of creation is within you. Without knowing that, you do not know much about yourself. So when the very source of creation is within you, self-realisation means befriending the Creator within you. And if the Creator is your friend, what is your problem with life?
So how does one get there? If you want to go to a place where you have not been before, you naturally seek a guide. A Guru becomes relevant to you only when you have an aspiration to constantly enhance your life; when you want to touch dimensions within which you yourself have not been able to touch. When people hear the word "Guru", they may have a lot of resistance, essentially because of the misuse of the word. A Guru is like a road map. If you want to travel uncharted terrain, do you go without a road map? You can; maybe you will anyway reach there. But there are also chances that to reach a destination which is right next to you, you may go around the world and come back, or you may never get there.
When you want to walk uncharted terrain, choose a person who has already walked the terrain. A Guru has already walked the path, so you are just seeking guidance; you are using him as a live road map. "Can't i do it without a Guru?" ^ Definitely you can, but what could be done in a short span of time, you may take lifetimes to do it. When the guide is about the inner dimension, we call him Guru because ^ "Gu" means darkness, "Ru" means dispeller ^ the word Guru essentially means one who dispels the darkness (within).
Why a Guru becomes essential when it comes to inner dimensions is because your whole perception of life is through the five senses. If you look at these five sense organs, you can clearly see that all of them are outward bound. But now you want to look inward in a completely different way. Because you do not have this perception right now, the inner dimension is not visible to you, so you seek help. Let's say you need surgery to be done.
You go to a surgeon, because you trust that he will do it better than you. Self-realisation is a much deeper surgery than your doctor does. Your doctor cuts only the physical body; but here, you have to cut through many layers of your own misunderstandings and misperceptions. If you are trapped in a prison and you want to get out, it is good to have outside help. Bondage is an inside job, you need outside help for liberation. That is where a Guru fits in.