Lecture 4: Astrology (and why it's nonsense)
ASTR 1P01 - Lecture 4: Astrology (and why it's nonsense)
Introduction
The lecture discusses several key points:
The relationship between astronomy and astrology.
.How to use the scientific method, critical thinking, and skepticism to demonstrate that astrology is incorrect.
Reasons why billions of people still believe in astrology, despite overwhelming evidence against it.
Astronomy and Religion
Ancient perspectives:
In ancient times, people lacked scientific knowledge and did not understand natural phenomena such as storms, earthquakes, volcanic eruptions, droughts, and diseases.
Without rational explanations, there was a belief that gods controlled various natural events.
Theological interpretations:
In many ancient cultures, natural disasters were often perceived as punishments from displeased gods.
Some people maintain these beliefs even today, despite scientific explanations.
Celestial observations:
Ancient cultures viewed the night sky as filled with fixed glowing dots, forming shapes resembling animals, people, or objects, leading them to assume these patterns had meanings.
They recognized seven moving celestial bodies:
The Sun
The Moon
Mercury
Venus
Mars
Jupiter
Saturn
These celestial bodies appeared to move in intricate paths, adding to the mystery of the heavens.
Divine associations:
There was a tendency for cultures to associate the seven moving celestial bodies with gods.
This practice can be traced back to at least 2600 BC with the Sumerians and was reflected in various cultures worldwide.
Examples of celestial deities:
Ra - Egyptian God of the Sun
Shamash (Utu) - Mesopotamian God of the Sun
Helios - Greek God of the Sun
Luna - Roman Goddess of the Moon
Chandra - Hindu God of the Moon
Igaluk - Inuit God of the Moon
Religious beliefs and weekly calendar:
Modern religions still claim that their gods reside in the heavens, often without specific celestial associations.
The seven days of the week were named after these seven celestial bodies and their deities.
Examples include:
Sunday - Day of the Sun
Monday - Day of the Moon
Tuesday (French - Mardi) - Mars
Wednesday (French - Mercredi) - Mercury
Thursday (French - Jeudi) - Jupiter
Friday (French - Vendredi) - Venus
Saturday (French - Samedi) - Saturn
In English, Saturdays still bear Saturn's name, while other days derive from Norse counterparts.
Influences on daily life:
Celestial bodies influenced human lives, shaping behaviors due to the Sun providing light, warmth, and seasonal changes, while the Moon affected tidal patterns.
Ancient astronomers documented these correlations, recognizing cycles marked by stars and constellations in relation to agricultural practices.
The Birth of Astrology
Origin of astrological thought:
The association of celestial entities with deities led to interpreting the divine will through celestial observations for signs or omens.
The movements of celestial bodies and extraordinary astronomical events like eclipses were believed to convey divine messages.
The beginnings of astrology are estimated at least 5,000 years ago with the Sumerians, likely much earlier.
Babylonian contributions:
The oldest known astrology system is Babylonian astrology, which emerged around 1800 BC.
Evidence includes Enuma Anu Enlil, a series of 70 clay tablets from around 1600 BC, documenting interpretations of celestial and other natural omens.
Methods of interpretation:
Babylonian priests employed two main methods:
Abstract association: Correlating celestial events with certain occurrences, e.g., an early new moon as a bad omen suggesting premature events.
Historical correlations: Observing and linking celestial phenomena with historical events (e.g., a new moon's rise correlating with victory in battles).
Cultural Spread:
Babylonian astrology disseminated globally, including into Egyptian, Greek, Roman, and Islamic cultures.
Other cultures, such as Hindu and Chinese civilizations, developed their distinct astrological systems independently.
Greek advancements:
By around 200 BC, the Greeks expanded astrology to influences on individuals, introducing natal astrology, where celestial arrangements at birth would shape personality and fortunes.
Ptolemy's Influence:
In the 2nd century, Ptolemy authored the Tetrabiblos, detailing astrological techniques and philosophy prevalent in his time.
Astrology vs. Science
Ptolemy’s Almagest:
Considered the classical work in astronomy, has been proven incorrect due to its geocentric model and inaccuracies.
Consequently, it is no longer regarded as an authoritative astronomical resource.
Validity of Tetrabiblos:
Similarly, Tetrabiblos is deemed incorrect and the claims are systematically disproven by modern science.
Despite this, it underpins contemporary Western astrology practices.
Defining characteristics of science vs. astrology:
Astronomy is classified as a science due to its evolving nature, discarding outdated theories based on empirical evidence.
Astrology, in contrast, is labeled as a pseudoscience; it does not rely on the scientific method and typically remains untested.
Correlation vs. causation:
Babylonian methods hinted at relying on correlation to imply causation, a misconception since correlation does not equal causation.
Modern scientific hypotheses require not only correlational evidence but also mechanisms to explain why events influence each other.
Absence of hypothesis testing:
Without hypothesis testing or experimental validation, astrology lacks a scientific basis.
Accurate scientific theories generate predictions that can be tested; astrology does not and thus fails to evolve.
The nature of coincidences:
Many claims of astrology are shown to be coincidences. If predictions are incorrect, a scientific approach mandates discarding false hypotheses, a practice absent in astrology.
Psychological drivers:
Factors such as confirmation bias can influence astrologers to inaccurately retain their hypotheses and maintain support for astrology despite contradicting evidence.
Manipulation by authority:
Babylonian priests arguably exploited astrology to guide rulers, further influencing widespread belief systems.
Importance of understanding astrology:
Studying astrology emphasizes the necessity of scientific literacy and discerning fact from fiction, which can have profound implications for decision-making processes in life-threatening scenarios.
Evidence Against Astrology
Four reasons astrology is disproven:
It is founded on incorrect assumptions.
It lacks a mechanism of action.
There is indirect evidence against it from unrelated studies.
Direct evidence from studies specifically designed to test it shows no correlation.
Incorrect Assumptions
Foundational beliefs:
Natal astrology relies on horoscopes, representing celestial positions at birth.
The zodiac is divided into 12 signs, named after corresponding constellations.
Sun sign: Position of the Sun at the time of birth, most recognized in astrology.
Moon sign: Position of the Moon at birth.
Rising sign (ascendant): The sign on the eastern horizon at birth.
Historical background:
The zodiac was categorized by the Babylonians around 400 BC, despite modern knowledge of axial precession, which alters star positions over time (full rotation every 25,700 years).
Misalignment issues:
The positions of stars and signs have shifted, thus the actual Sun sign can differ from the one used in astrology.
Astrologically, if born on certain dates, your sign may differ from reality, leading to incorrect assertions regarding personality traits.
Existence of a 13th zodiac sign:
Ophiuchus (off-ee-YOO-kus) exists as a 13th constellation of the zodiac, indicating further difficulties in categorizing astrology accurately.
Subjectiveness of division:
The Babylonians allocated signs based on an arbitrary choice relative to the lunar-month and could have established a 13-sign division.
The modern classification of 88 constellations is also arbitrary, further underscoring the lack of objective meaning in astrology.
Illusive motions:
Retrograde motion is an apparent phenomenon where planets seem to move backward, though it is just an optical illusion without physical significance.
Planetary implications:
Birth situations on different planets or solar systems would show vastly different celestial arrangements, calling into question astrology's universal assumptions.
Scientific understanding:
Understandings of human development reveal that the moment of birth does not uniquely influence personality; it is rather a continuous process influenced by genetics and environment.
Conclusion on assumptions:
Astrology rests on numerous foundational errors such as geocentric modeling, static sky perspectives, arbitrary zodiac divisions, and oversimplified interpretations of planet influences.
Absence of Mechanism of Action
Personality determinants:
Individual personality significantly stems from genetics and family environment, as evidenced by studies on identical twins raised in different settings.
Some traits remain consistent regardless of environmental differences, emphasizing that genetics predominantly influence personality.
Astrological deficiencies:
Astrology neglects to provide any explanatory mechanism linking celestial positions with personality or events.
Scientific hypotheses should have defined mechanisms, allowing for predictive capabilities tested through experiments.
Indirect Evidence Against Astrology
Twins and personality:
Studies demonstrate that twins born minutes apart can differ significantly in personality, challenging astrological claims.
The expected uniformity in personality traits among twins under astrological reasoning fails to manifest in reality.
Genetic influence:
Analysis shows identical twins with shared genetics present more similarities than non-identical twins, casting doubt on astrology as a personality predictor.
Direct Evidence Against Astrology
Scientific studies:
Since the 1950s, numerous controlled studies have examined astrology's validity.
Notably, an experiment by Shawn Carlson (1985) with 28 leading astrologers involved personality assessments based on birth data.
Experimental setup:
Participants completed personality tests, and astrologers were tasked with identifying the correct results from multiple options.
Astrologers performed only at random chance levels, pointing to a complete lack of correlation between zodiac signs and personality.
Comprehensive analyses:
Reports from Geoffrey Dean and Ivan Kelly (2003) surveyed over 40 similar studies confirming astrology's lack of empirical credibility, equating its accuracies to random guesses.
Psychological Factors and Beliefs
Beliefs formation:
Millions continue to uphold their belief in astrology regardless of scientific contradictions.
The absence of critical thinking and skepticism skills contributes significantly.
Critical thinking allows for rational analysis of arguments and evidence, while skepticism involves requiring evidence for claims.
Educational gaps:
Many people receive no formal training in critical thought or skepticism, relying solely on intuition and unfounded beliefs.
Examples include prevalent claims in religion, alternative medicine, and even conspiracy theories.
Consequences of misinformation can be dire, as seen during the COVID-19 pandemic where misinformation considerably affected vaccination rates and health outcomes.
Statistical correlations:
Marketing campaigns and campaigns of public health emphasize the importance of critical reasoning in navigating current issues.
Fallacies and Biases in Belief Systems
Cognitive biases:
Recognition of logical fallacies and cognitive biases is essential for effective critical thinking.
The Barnum effect explains the tendency of individuals to accept vague personality assessments as uniquely applicable to themselves, a technique commonly exploited in astrology.
Experimental insights:
An experiment by Forer (1948) involving psychology students provided the same generalized assessment to all, yet individual ratings remained high due to the generic nature of statements.
Confirmation bias examples:
Individuals recall instances confirming astrological predictions while disregarding those that contradict them, reinforcing their belief systems.
Logical fallacies:
Fallacies in astrological claims include:
Correlation implies causation: Misinterpreting events that correlate as causational.
Post hoc reasoning: Assuming causation based on sequential timing.
Anecdotal evidence: Relying on personal success stories as universal truths.
Appeal to tradition: Using longevity as evidence of validity.
Appeal to popularity: Citing widespread belief as proof.
False authority appeals: Relying on a celebrity's belief.
Faith appeals: Suggesting faith is necessary despite contradictory evidence.
Resources for learning:
Lists of logical fallacies and cognitive biases can be found online for those looking to improve their analytical skills.
Reliable Sources for Astronomy
Recommended reliable resources include:
Wikipedia (with caution for citation checks).
Encyclopedia Britannica.
Reputable space agencies (NASA, ESA, etc.).
Observatories conducting experimental research (e.g., Hubble, JWST).
Academic astronomy textbooks.
Select popular science literature and university web resources, while exercising caution with online platforms like YouTube.
Conclusion
The lecture concluded with an evaluation of the differences between:
Astronomy: A science grounded in evidence.
Astrology: A pseudoscience debunked by empirical evidence.
Encouragement towards cultivating critical thinking skills and understanding scientific principles.
Suggested reading: OpenStax astronomy, section 2.3, alongside available practice questions in the textbook and course website.
Here are the answers to your questions:
The Sumerians, around 2600 BC, are thought to be the first to associate gods with celestial bodies.
Shamash (Utu) was the Mesopotamian god of the Sun.
The planet Mercury is associated with Wednesday (Mercredi in French).
Yes, celestial bodies do influence our lives. The Sun provides light, warmth, and seasonal changes, while the Moon affects tidal patterns. Ancient astronomers also recognized cycles marked by stars and constellations in relation to agricultural practices.
The two methods used by Babylonian priests to interpret astronomical events were:
Abstract association: Correlating celestial events with certain occurrences (e.g., an early new moon suggesting premature events).
Historical correlations: Observing and linking celestial phenomena with historical events (e.g., a new moon's rise correlating with victory in battles).
The ancient book that forms the basis of modern astrology is the Tetrabiblos, written by Ptolemy in the 2nd century.
False. Due to axial precession, the positions of stars and signs have shifted over time, meaning the actual Sun sign (where the Sun was at your birth) can differ from the one used in astrology.
Four arguments against astrology are:
It is founded on incorrect assumptions (e.g., geocentric model, arbitrary zodiac divisions).
It lacks a mechanism of action to explain how celestial positions could influence personality or events.
There is indirect evidence against it, such as identical twins born minutes apart having significantly different personalities.
Direct evidence from controlled studies (like Shawn Carlson's 1985 experiment) shows no correlation between zodiac signs and personality, with astrologers performing only at random chance levels.
Horoscopes often seem to apply to you personally because of The Barnum effect. This is the tendency of individuals to accept vague, generalized personality assessments as uniquely applicable to themselves, even though they could apply to almost anyone.
An example of confirmation bias, other than the ones given, is: A person who believes that Friday the 13th is an unlucky day might only remember unfortunate events that happened on that date, while forgetting all the times nothing bad occurred, or unfortunate events that happened on other dates.
An example of the appeal to false authority fallacy, other than the ones given, is: A professional athlete endorsing a particular brand of a health supplement, despite having no medical or scientific expertise to evaluate its effectiveness.
The main differences between astronomy and astrology are:
Astronomy is a science that relies on empirical evidence, the scientific method, and evolves by discarding outdated theories. It generates testable predictions.
Astrology is a pseudoscience that does not rely on the scientific method. It typically remains untested, lacks a mechanism of action, and is based on incorrect assumptions. Its claims are systematically disproven by modern science, and its accuracies equate to random guesses.