How does a new hypothesis replace an older explanation of something in the natural world

How does a new hypothesis replace an older explanation of something in the natural world? To understand this let us look at one of the classical example of geocentric theory and heliocentric theory. The geocentric theory states the Earth is at the centre of the solar system and the Sun, Moon, and all the other planets revolve around it. This ancient theory failed to explain the phenomenon like the phases of Moon, solar eclipse and lunar eclipse. The modern heliocentric theory which states that the Sun is at the centre of solar system, and all the planets including the Earth revolve around it. This theory was able to explain all the phenomenons unlike the geocentric theory. Hence the heliocentric theory replaced the geocentric theory. In short, when the new theory is able to explain all the observed phenomenon and predict their occurrences correctly, is deemed to be complete until any new unique observations are made. This way the older incomplete theory gets replaced by the newer one.

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