As magma pushes toward Earth’s surface, pressure on it decreases, and gases like carbon dioxide and sulfur dioxide once held within the magma escape like the bubbles of carbon dioxide you see in an opened carbonated beverage. The extruded fluid that emerges to form volcanoes like Mt. St. Helens and widespread lava flows like the Columbia River Plateau is different from the source matter.
Like magma, our hidden character lies within and under great pressure. We can’t let it surface, or everyone will see our underlying composition. Some of that composition is dissolved in the underlying matter of our being. Even in outbursts of anger, ejected like lava during an eruption, we show the world something different from what lies hidden, something different because it can’t contain all that we secretly are. The extruded lava of personality is different from the magma of fears, insecurities, and desires.
Each of us might give some hints to our basic composition in our daily extrusion of emotions and behaviors, but generally, what lies below doesn’t surface as the same substance. Draw this analogy: On any planet the release of those hidden components affects more than just the surrounding rocks and local ecology. Earth’s entire ecosystem can be affected by big eruptions. The giant eruptions of super volcanoes like Yellowstone and Toba altered climate and life over large regions.
Typically, any release of our own hidden components can influence others. Those components, long hidden in the depths of our psyche’s chambers, can, upon being brought to the surface, alter our own lives as well, but possibly for the worse.
Magmas differ in composition, so not all lavas are the same. Some magmas exit the ground as fast-flowing and copious basaltic lavas like those in the Hawaiian Islands. Other magmas exit as pasty, viscous matter that is often associated with explosive eruptions like those of Mt. St. Helens in the USA and Pinatubo in the Philippines. Note something else: Magma chambers are themselves complexes of different components capable of producing different lavas during different eruptions. So also, psychic magmas exit as different compositions, either explosively or fluidly. In both instances, what appears at the surface is an altered form of what lies beneath.
Just as volcanologists sample hot lavas to ascertain their magmatic composition, we take samples of our extruded psyches to interpret the nature of the hidden, dissolved components. We can get a good idea of what lies below, but we have to do some extrapolating. As long as we understand the nature of our Self-understanding we can find the sampling somewhat, but not absolutely, useful or true.