An alchemical diagram from the 'Utriusque Cosmi, Maioris Scilicet et Minoris, Metaphysica, Physica, atque Technica Historia' by Robert Fludd, showing man as the solar system: his heart is the sun. 'Dies Microcosmicus', 'Nox Microcosmica' is written above and below the man. The Hebrew name of God or tetragrammaton 'Yahweh' is written in a cloud above his head, and a series circles radiate from the genitalia - the center of life. Circa 1617. Robert Fludd, also known as Robertus de Fluctibus (1574-1637) was a prominent English Paracelsian physician, astrologer, mathematician, cosmologist, Qabalist, Rosicrucian apologist.