Clearly imagination must be the source from which astronomy•cal theories are developed about the cosmos that surround us.  But according to Sagan, skepticism is the very tool to keep things in check, helping to filter out the fantasy from reality.

We live in a world that can at times feel overwhelming and simply larger than life.  But what is worth keeping in perspective is the thought that we as a human race could be compared to something like a “Mote of dust.”  I prefer, for example purposes, a gnat standing upon a grain of sand.  A grain which lies on miles of surrounding desert.

As this gnat, we have only ventured to jump to a few of the surrounding granules and have somehow developed this sense of knowledge of the entire desert around us.  Sure, our small group of sand granules have demonstrated certain characteristics from which we can feel comfortable proclaiming certain principles and theories about, but we simply cannot make viable assumptions about the desert from a few granules in our proximity.

Massive land-based mirrors, the Hubble telescope, lunar landings and interstellar travel by roving robots have given an unbelievable amount of information and observations about our immediate “granules” but characteristics of our local cosmic neighborhood cannot be assumed throughout the massive universe as a whole.

There may be a dust storm or raging winds on the other side of our desert and based on our location, we simply would not be aware of this fact based purely on measurable scale. If the desert metaphor doesn’t work for you, think of our exploration (to this point) as a bustling metropolis. Our solar system is our neighborhood and the city around us could represent the distances we’ve traveled, both physically and by way of telescopes, rovers and scientific tools we currently have at our disposal.

Remember the first time you traveled to another country and how drastically different things were on foreign soil?  Things we thought we understood and accepted as constants quickly became obsolete.  Wouldn’t this happen to us even on a scientific level if we ventured beyond our metaphorical city?

In a universe in which we cannot determine an exact moment of beginning (singularity) and have no reasonable grounds to claim we know of an exact moment or measure of ending (boundaries of our universe), how are we to speculate that the laws and principles we find true to our surroundings should apply to unknown distances both in the past (origins of our universe) and the bounds of our future and the surrounding universe?  One key, and third, factor that must be incorporated into Sagan’s two underlying elements of exploration must be scaled perspective.