Swami Vivekanand had beautifully and simply enunciated the theory of Cause and Effect; Cause being just a means to an end and Effect being the outcome.
This theory is a part of spirituality and mysticism.
Minds of both Wolfgang Pauli and Carl Jung served as gestation chambers for the theory of Synchronicity which was later studied by Jung in the light of Astrology.
The Pauli Effect was coined to describe a phenomenon where technical equipment will become dysfunctional in the presence of Wolfgang Pauli.
Supposedly, the effect was so strong that Otto Stern had banned Pauli from entering his lab despite their healthy relations.
Pauli then collaborated with Hans Bender and Carl Jung and thus, Synchronicity was born.
Jung describes it as, “temporally coincident occurrences of causal events”.
In simple words, it is a phenomenon used to describe a causal relation between two isolated events that occurred simultaneously and there is no apparent and patent cause to connect them.

Thinking about someone and they appear on your doorstep after a while is an example of synchronicity.
How Synchronicity is related to Astrology?
Jung sees everything that appears to happen randomly is actually connected with some events making a chain of cause and effect. This notion is in consonance with astrological principles which believe that the universe is affected by unseen forces.
These invisible forces are responsible for causing events in a person’s life.
This characterization of force is analogous to astrology and dictates the influence of astrology in Jungian Psychoanalysis.
We can conclude its definition by holding that events happening in a person’s life is somewhere connected with whatever happens in the universe.
This is may not appeal to scientific minds, but it holds in the theory of Quantum Entanglement.
Quantum Entanglement is a theory in which two quantum particles are spatially different from each other but their state can be defined with respect to each other according to a piece of news from The Herald.
Astrology and Jung
Carl Jung considered the study of astrology as an ancient study of psychology.
The twelve zodiacs represent forces of nature that influence the psyche of a person. To him, astrology was a collective unconscious, where planets are considered gods and symbols as the archetype.
Thus, zodiacs were a part of the archetype.
He was sure that each human being possesses a psychic power of knowing about themselves which is often manifested in their dreams.
We are born with this inherent ability and it cannot be built or acquired. Astrologers believe that every person is inclined to acquire a certain lifestyle.
It is his innate inclination that draws him towards this irrespective of his surroundings.
Jung believed that the knowledge that person seems to know already is passed down from ancestors; the theory is popularly known as Genetic Memory or Neuropsychology.
Jung believed that zodiac signs and planetary motions are responsible for the personality traits of a person.
These archetypes and any movement in them influence human behavior instigating them to take a certain course of action.

For him, astrology was an ‘Intuitive Method’.
In an interview held in 1954, he explained that he was able to verify and correlate certain universal events and isolated events with planetary movement, especially when Saturn and Uranus were in question.
He used to draw horoscopes of his patients to know more about their psychological state of mind.
Jung and Astrological Synastry
Jung elucidated an experiment he conducted in his book synchronicity. He demanded the production of 400 pairs of horoscopes of married couples.
He randomised half of them and tried to find out the correct partners.
He found that people married the one who was astrologically compatible with them.
In astrology, this correlation is known as Astrological Compatibility. In Hinduism, natal charts of people wanting to marry are perused.
Predictions are carried out in two ways, i.e., by matching the natal charts and ninth sub-chart known as ‘Navamansa’ and matching the constellations based on the moon sign of each person with the other.
Jung was astonished to have predicted correctly.
He repeated the experiment by changing methods and found similar results. He could not identify it with mere coincidence and could not find any plausible connection with the findings of his experiment.
This is why he named synchronicity as ‘a acausal relationship.