The shift from the theory that the Sun goes around the Earth (geocentrism) to the theory that the Earth goes around the Sun (heliocentrism) is an example of a paradigm shift.

Here's why:

* A paradigm shift is a fundamental change in the basic concepts and experimental practices of a scientific discipline.

* The geocentric model, championed by Ptolemy, was the dominant scientific understanding for centuries. It explained many observations, but had some inconsistencies.

* The heliocentric model, proposed by Copernicus, was a radical departure from the accepted paradigm. It challenged the prevailing view of the universe and required a complete rethinking of astronomy.

* This change was not just about swapping one model for another; it involved a complete shift in how scientists understood the universe and how they conducted their research.

Therefore, the transition from geocentrism to heliocentrism is a classic example of a paradigm shift in scientific thought.