A reassuring way to validate our existence, yes? Yet the validation is incurred to the thinker himself: hardly an improvement on Descartes's Cogito, ergo sum as the thinker only clarifies his reality through further self-projection. Perhaps the use of material substance ensures that the mental projection of ourselves is indeed a physical reality, with the added appeal of not being forced to endure the imposition of outside sentience on our personally crafted, pseudo-reality. I think most will find that this added luxury will forever deny the mirror from being a true substitute for interpersonal relationships. Without the ability to transform our own thoughts we are stymied in a limited universe that's incapable of being either transformative or informative. Without other intelligence we may never see beyond the borders of our current selves; this must be at least an element of why all people crave people. Even the most isolated and seemingly alone.
Perhaps a rather esoteric and self aggrandizing way of explaining the need for a blog, yet isn't that the very purpose of web logs? To become self-focused, self-obsessed, or more positively at least self-aware? A journal serves as a private outlet and a place for personal reflection in the written form. Phone calls and conversations allow for an even exchange of ideas and emotions (though they by no means guarantee it). A blog though is by definition narcissistic. It declares that the day-to-day minutia of your life is not only worth writing down (perhaps only a statement on the importance of your time) but is important enough for others to read and respond to. Which of course is exactly what people do so perhaps this vanity is not without a corresponding reality.
Whatever the case may be, I have now joined the growing throng of bloggers, thus can not escape being by hit whatever criticism I or other may level at them.
Beware, O' soul of peril,
We run beneath the eyes
That seek to find the Heavens
And receive instead a herald
Of the dawn below the skies