At least some of these peculiarities of self-knowledge can be explained by taking self-knowledge to be a species of agent-relative knowledge.
There are two quite different ways of cognizing objects (people, things, places and times). We can think of them via their relationship to us, the role they are playing in our lives at the moment of thought: the object I see; the present moment; the place I'm at; the person I'm talking to. We need to think about things in the first way, when we are picking up information about them perceptually or interacting with them, since ways of knowing and acting are tied to these agent-relative roles. I can learn about the here and how by looking; I can learn about the person I am talking to by asking questions, etc.
But these agent-relative roles cannot be our only ways of thinking about objects of more than passing interest to us. Different objects play the same agent-relative roles at different times, and at any given time many of the objects we wish to retain information about will not be playing any agent-relative role for us. And we cannot accumulate information along such roles. Suppose I am in Tokyo on Tuesday but return to Palo Alto on Friday. From the facts that on Tuesday I truly thought ``Japanese is the official language here" and on Friday I truly thought ``Senator Stanford used to live near here" it does not follow that there is some place where Japanese is the official language and near which Senator Stanford used to live.
In order to retain and accumulate information about objects, to construct and maintain a coherent picture of the world, we need to have a way of conceiving of objects as existing independently of us, as occupying and then ceasing to occupy various agent-relative roles. That is, we need objective ways of thinking about objects. We keep track of them by names or descriptions that do not depend on their relationship to us: Cordura Hall, 4 p.m., June 23, 1995, the southernmost town in Santa Clara County, Aurora Fischer. These serve as our fundamental ways of thinking about those objects. Recognition consists in connecting our objective ways of thinking of objects with the roles those objects play at a given moment. Consider the knowledge I might express with, ``Today is July 4th". This is knowledge that a certain day, objectively conceived (``July 4th") is playing a certain role in my life; it is the present day, the day on which the thinking and speaking take place. This kind of knowledge, ``knowing what day it is," is quite crucial to successful application of other, more objective knowledge. If I know that the party is on July 4th, and know that today is July 4th, then I will form the right expectations about what the day will be like.
Similarly, I may be in Kansas City, and know that Kansas City is a good place for a steak dinner. But if I don't know that I am in Kansas City, if I don't realize that Kansas City is playing the ``here" or ``this city" role in my life at this moment, I won't be able to apply the knowledge that Kansas City is a good place for a steak dinner.
And again, I may know that Aurora Fischer has important information about my schedule, but unless I realize that the person I am talking to is Aurora Fischer I will not apply this information, and say, ``Can you tell me where this afternoon's meeting is?"
These kinds of knowledge are, like self-knowledge, ``essentially indexical". We use ``now" and ``today" to express our knowledge of what time it is, and ``here" to express our knowledge of where we are. These locutions are not reducible to names or objective descriptions, just as ``I" was not. I cannot express what I say when I say, ``The meeting starts right now" by saying ``the meeting starts at D" for any description D of the present moment.
We are also immune to certain sorts of misidentification when we use certain methods of knowing. There is a way of finding out what is going on around one, namely opening one's eyes and looking (Evans, 1985). Now when one learns what is going on in this way, one can hardly fail to identify the time at which this is happening as now and the place as here. And finally, the forms of thought we express with ``now" and ``here" seem to have a unique motivational role. If I want to do something here and now I will simply do it.
So, to summarize. We cognize things, times and places not only objectively, but via their present relationship to us--via agent-relative roles. There are ways of knowing and acting that are tied to such roles, and our knowledge exhibits immunity to misidentification relative to such roles. And knowledge via such roles plays a special motivational role. Finally, because different objects play these roles in our lives at different times, it is invalid to accumulate knowledge along them.