Calvin wanted to denounce any causative link between the position of the stars in the sky and a specific event – happy or tragic – in everyday life, and any interpretation supporting God’s predetermination for the righteous or the sinner.

He showed that this hypothesis had no scientific basis, and moreover that it had no theological or biblical basis.

“Contenders who wanted to over-interpret natural astrology, pretending it was a skill, have devised another sort of astrology called judiciary, based on two main principles ; firstly to know not only the nature and character of men, but also their adventures… and all they have to do or suffer throughout their lives ; secondly, the outcomes of their deeds (p112) in the warning against judiciary astrology…” (Œuvres françaises, p107-134, Paris, 1842)