Explain the differences between the Ptolemaic view of the universe and the new vision of the universe proposed by Nicolaus Copernicus. Read the following excerpt from Galileo: ... for the holy Bible and the phenomena of nature proceed alike from the divine Word, the former as the dictate of the Holy Ghost and the latter as the observant executrix of God's commands. Identify Galileo's main argument here.

The Ptolemaic view of the universe was geocentric: the Earth was at the center of the Universe, the Moon, Mercury and Venus circled around the Earth in that order, the Sun and the rest of the planets were after, and the starts were located far beyond.

The model of the Universe according to Nicolaus Copernicus was heliocentric: the Sun is at the center of the Universe, the Earth and the other planets circle around it, and the stars are far away and fixed.

What Galileo means by the statement is that neither model was incorrect, or sinful. The universe was created by divine intervention, and humans try to understand its shape. The Ptolemaic approach was an initial understanding of the divine creation, and the Copernican view was more advanced.