Western esotericism
Renaissance and Early Modern period

During the Renaissance, a number of European thinkers began to synthesize " pagan " (that is, not Christian) philosophies, which were then being made available through Arabic translations, with Christian thought and the Jewish kabbalah. The earliest of these individuals was the Byzantine philosopher Plethon (1355/60–1452?), who argued that the Chaldean Oracles represented an example of a superior religion of ancient humanity that had been passed down by the Platonists.

Plethon's ideas interested the ruler of Florence, Cosimo de' Medici, who employed Florentine thinker Marsilio Ficino (1433–1499) to translate Plato's works into Latin. Ficino went on to translate and publish the works of various Platonic figures, arguing that their philosophies were compatible with Christianity, and allowing for the emergence of a wider movement in Renaissance Platonism, or Platonic Orientalism. Ficino also translated part of the Corpus Hermeticum, though the rest was translated by his contemporary, Lodovico Lazzarelli (1447–1500).

Another core figure in this intellectual milieu was Giovanni Pico della Mirandola (1463–1494), who achieved notability in 1486 by inviting scholars from across Europe to come and debate with him 900 theses that he had written. Pico della Mirandola argued that all of these philosophies reflected a grand universal wisdom. Pope Innocent VIII condemned these ideas, criticising him for attempting to mix pagan and Jewish ideas with Christianity.

Pico della Mirandola's increased interest in Jewish kabbalah led to his development of a distinct form of Christian Kabbalah. His work was built on by the German Johannes Reuchlin (1455–1522) who authored an influential text on the subject, De Arte Cabalistica. Christian Kabbalah was expanded in the work of the German Heinrich Cornelius Agrippa (1486–1535/36), who used it as a framework to explore the philosophical and scientific traditions of Antiquity in his work De occulta philosophia libri tres. The work of Agrippa and other esoteric philosophers had been based in a pre-Copernican worldview, but following the arguments of Copernicus, a more accurate understanding of the cosmos was established. Copernicus' theories were adopted into esoteric strains of thought by Giordano Bruno (1548–1600), whose ideas were deemed heresy by the Roman Catholic Church, which eventually publicly executed him.

A distinct strain of esoteric thought developed in Germany, where it became known as Naturphilosophie. Though influenced by traditions from Late Antiquity and medieval Kabbalah, it only acknowledged two main sources of authority: Biblical scripture and the natural world. The primary exponent of this approach was Paracelsus (1493/94–1541), who took inspiration from alchemy and folk magic to argue against the mainstream medical establishment of his time—which, as in Antiquity, still based its approach on the ideas of the second-century physician and philosopher, Galen, a Greek in the Roman Empire. Instead, Paracelsus urged doctors to learn medicine through an observation of the natural world, though in later work he also began to focus on overtly religious questions. His work gained significant support in both areas over the following centuries.

One of those influenced by Paracelsus was the German cobbler Jakob Böhme (1575–1624), who sparked the Christian theosophy movement through his attempts to solve the problem of evil. Böhme argued that God had been created out of an unfathomable mystery, the Ungrund, and that God himself was composed of a wrathful core, surrounded by the forces of light and love. Though condemned by Germany's Lutheran authorities, Böhme's ideas spread and formed the basis for a number of small religious communities, such as Johann Georg Gichtel 's Angelic Brethren in Amsterdam, and John Pordage and Jane Leade 's Philadelphian Society in England.

From 1614 to 1616, the three Rosicrucian Manifestos were published in Germany. These texts purported to represent a secret, initiatory brotherhood founded centuries before by a German adept named Christian Rosenkreutz. There is no evidence that Rosenkreutz was a genuine historical figure, nor that a Rosicrucian Order had ever existed before then. Instead, the manifestos are likely literary creations of Lutheran theologian Johann Valentin Andreae (1586–1654). They interested the public, so several people described themselves as "Rosicrucian", claiming access to secret esoteric knowledge.

A real initiatory brotherhood was established in late 16th-century Scotland through the transformation of Medieval stonemason guilds to include non-craftsmen: Freemasonry. Soon spreading into other parts of Europe, in England it largely rejected its esoteric character and embraced humanism and rationalism, while in France it embraced new esoteric concepts, particularly those from Christian theosophy.
punctuation:no_comma