Premonitions tell you things that may come to be should the current pattern continue the way it is unfolding. As humans we have the power to change this. So no, nothing is set in stone... But it's possible to know the outcome of an event before it actually happens because everything follows a formula. It all gets rather complex but this is why we are able to know things before they happen. It's not definite because we can change the pattern by making a choice along the line we would not have made without "seeing ahead". Time and symbols are only part of the equation, there is really a lot more to it. When you finally do understand it, it isn't as complicated as it seems. It's very simply, but it's difficult to explain.