The power of belief. When we belief in something and have faith in it, it will start manifesting physically. When we think that something is possible, it will start resonating and happen. Believing in something creates an energy that doesn't appear to our eyes but it is there in some form, like an invisible skeleton of the thing that we belief in. Actually we are practising it in our daily lives without realizing that we do and one of them is that we go sleep at the end of the day with the belief that we will wake up the next day, although we are well aware that life is subjective and the reverse may happen. Therefore, I think that the most powerful thing in the world is the power of believing and when we do, we will get there no matter how far/high/difficult it is.