Basic element
Basic elements were the concept proposed to explain the complexity of all matter in terms of simpler substances, and were found in everything in existence. The Barkonians, a pre-industrial society from Barkon IV, believed that the basic elements of the universe were sky, fire, rock, and water.

In a school lesson taught by Talur, she explained that these basic elements "can be found in every object, every person, every animal, everything. The rock in this wood can be felt by its weight and by its hardness. If we expose the wood to flame, we can encourage the fire within the wood to show itself. We can also see smoke, which is a part of the sky. The water in wood is difficult to see. Sometimes the elements are buried deep within the objects, but the four elements are always there." 

Jayden, who was in reality the amnesiatic Soong-type android named Data, upon hearing Talur's explanation, told her that he did not believe her reasoning to be correct. He explained that, "I believe you are reasoning by analogy, classifying objects and phenomena according to superficial observation rather than empirical evidence." He further elaborated that "Wood, for example, does not contain fire simply because it is combustible, nor does it contain rock simply because it is heavy. Wood, like any complex organic form, is composed of thousands of different chemical compounds, none of which is fire." 

Talur stopped Jayden at that point, and reminded everyone of his memory loss; Jayden, nonetheless, later told his friend  that he still did not agree with Talur's assessment, admitting, "Although I do have gaps in my memory, I know that fire is not an element." ()

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