Queen Elizabeth openly expressed her admiration for his work. In Oxford Giordano gave lectures on the immortality of the soul and the doctrine of reincarnation as well as on the Copernican theory. Giordano declared that Space is filled with a countless number of solar systems, each with its central sun and planets. These suns, he said, are self-luminous, while the planets shine by reflected light. That was not the only dogma he questioned.
Nature is a living unity of living units, in each of which the power of the whole is present.
Nature, therefore, must never be conceived as a creation. Back in Paris, Bruno presented 120 theses in which he warned the French against the dangers of blind belief asking them to bend their heads only before the truth. He went to Germany to visit some university towns, but met with hostility. At the Frankfurt fair he met two Italian booksellers. They took some of his books to Venice.