Bruno was the first fully to grasp the importance of the Copernican hypothesis, to perceive its issues and to adapt it to the formation of a new ontology.
Copernicus, though he proclaimed the central position of the sun in our system, had not ventured to maintain the infinity of the universe.

For him, as for the elder physicists, there remained a sphere of fixed stars inclosing the world perceived by our senses within walls of crystal.
Bruno broke those walls, and boldly asserted the now recognized existence of numberless worlds in space illimitable.

His originality lies in the clear and comprehensive notion he formed of the Copernican discovery, and in his application of its corollaries to the Renaissance apocalypse of deified nature and emancipated man.

The deductions he drew were so manifold and so acute that they enabled him to forecast the course which human thought has followed in all provinces of speculation.
This leads us to consider how Bruno is related to modern science and philosophy.

The main point seems to be that he obtained a vivid mental picture (_Vorstellung_) of the physical universe, differing but little in essentials from that which has now come to be generally accepted.