The word occult comes from the
Latin occultus (clandestine, hidden, secret), referring to "knowledge of the hidden". In the
medical sense it is used commonly to refer to a structure or process that is hidden, e.g. an "occult bleed."The word has many uses in the
English language, popularly meaning "knowledge of the
paranormal", as opposed to "knowledge of the
measurable", usually referred to as
science. The term is sometimes popularly taken to mean "knowledge meant only for certain people" or "knowledge that must be kept hidden", but for most practicing
occultists it is simply the study of a deeper spiritual reality that extends beyond pure reason and the physical sciences. The terms
esoteric and arcane can have a very similar meaning, and the three terms are often interchangeable.
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