How much can we trust our own unique, subjective experiencing?
Science deals with things that can be both shared and measured- tables, for example. Other things exist which can be shared but not easily measured- feelings such as happiness and fear, for example. Most people have experienced these things and accept that they exist but the actual subjective experience itself cannot be measured (although chemical states in the body associated with them can be).
There exists a third category: experiences that are not readily shared with others because they are unusual, such as experiences had whilst in an altered or unusual state of consciousness. The “reality” of these things is up to the individual to decide. The potential for self-deception must be considered. The question is: how much do we trust our own mind and our own interpretation of events? The answer to this will depend on how we currently view past experiences we have had when we have had unusual experiences or insights. If we find that later on (when we are in a more conventional state of mind) our previous insights still hold water then this will enhance our trust in our own experiencing. However, when we are dealing with the subjective realm it is difficult to be certain of the validity of our experiences or the conclusions we draw from them due to the private nature of the experience and an inability to compare our experience to others. However, this doesn’t mean we should ignore them.
Ultimately all knowledge must come subjectively as this is truly the realm in which we* exist although we may seem to occupy an objective body in an objective universe! "Objective" objects (physical forms) only make up a small proportion of "objects in consciousness" and should not be given any greater importance than those things which remain private to ourselves- our thoughts and feelings- which are as real as anything that can be physically demonstrated!
*By "we" I mean consciousness, or awareness, which I have equated with the self.