I'm not really sure where I stand, since I see validity in either angle depending on the context that is relevant at the time.
I think naturally I'm more like Descartes (to borrow your ref), but I also firmly believe that it's easy to picture oneself any way one would like internally, while not behaving in ways that conform to that inner identity... so in a sense the internal identity then is naught but a fantasy and self-delusion if it is never made manifest (if we consider both internal and external landscapes to be part of the world that an individual inhabits)... at least in terms of character.
And reality of who we are to ourselves might not be the reality of who we are to someone else, realistically.
True, the latter is an assumption. Does it matter if no one else perceives the person we perceive ourselves as? And who does it matter to? And does that vary from person to person?Another point: Supposing that there is an internal view of self that runs in constrast to outer behavior, I think it is important to consider the question of how to "prove" it, or how to verify it. If all we have to go on is a person saying "Inside, I am person XY", it would seem to me to be unfalsifiable. Of course, I am assuming verifiability and falsifiability as being "important."
Since we cannot get access to someone's mind directly (at least at this time), it seems the only indication we have of someone being who they say they are is their observable actions (and the motivations they express for said actions).
That's true as well. My own concept of validity would suggest whichever view happens to give the more "consistent" description of the person. I'm more of a pattern mapper that notices imbalances within the pattern, rather than checking each point empirically (although I think that is important in order to cross-confirm conclusions).Before this question can be answered, I think it is important to consider whether or not there is commonly agreed upon way of measuring validity. Using myself as an example to illustrate, my inclination towards externally derived notions of "self" are in large part of a general inclination I have towards empirical methods of verification (and also perhaps due to my almost absence of "Fi"). Not everybody gives as much weight to this method, however.
My Fi sense has gotten stronger but for many years I didn't have much of an internal ego. I knew what I felt and what I wanted to believe about me but felt the need to validate my internal experience through external means.... which left things in a lot of turmoil for years. it also makes one extremely susceptible to the opinions and observations of others, right or wrong. It seems that to some degree one must develop Fi sense merely to have a holistic sense of self, instead of constantly having to 'step outside' to acquire one...