Isn't the light of knowing shining right now? Did you do anything to turn it on? Can you turn it off? Isn't knowing your very nature? Isn't the subject of all experiences itself that obvious aware-ness?
To try to quantify the subject is to attempt to objectify it. To put it in some terms which are understandable. Yet the subject of this very experience isn't locatable, it isn't to be found by descriptions. It is simply present without being some "thing" you are aware of. It IS you, isn't it?
When we say "I AM" we are confirming this light of knowing, this subjectivity or "awareness" - we are already intimately familiar with it, yet we either conceptualize it or go in search of it.
The subject of all experience is the knowing itself - an object upon which to apply the label "subject" can never be located. The subjective presence isn't describable in terms of space - there is nowhere we can say it is - we cannot say it stands anywhere in space. It's a mysterious presence which is the capacity of experiencing - but the mind doesn't like what it cannot describe, therefore many identifications (imagination) come about, an attempt to place that mysterious self-presence somewhere in space.
In the same way, that subjective presence cannot be located in time - it has no beginning nor ending. It doesn't start when a thought starts - on the contrary it is there to observe the beginning and ending of thought - once that thought ends it is ready for the next thought to begin. It is the reality between thoughts.
This light or activity or capacity of knowing is so simple and obvious that it is overlooked, conceptualized away, too simple. Because it cannot be quantified it is dismissed immediately - in the search for something tangible, some experience which might validate our search for peace and happiness.
But that light of knowing is itself the peace and happiness we long for. Peace and happiness are just words which really mean - the absence of conditions. In that light of knowing, no conditions are there before knowing can happen - like a mirror which reflects because reflecting is it's very nature - the experiences are registered because that is your very nature - unconditionally - effortlessly.
Stop right now and notice that knowing is happening - notice that it is always the ultimate subject beyond even the body and mind. It is even subjective to time and space, outside of their grasp. It has no attributes - it has no conditions. It simply IS.
What you have been seeking has always been there, the very capacity by which the search is known, the light by which any experience is illuminated. It is truly your own Self.