Joseph Jastrow

Joseph Jastrow (1863–1944) was a Polish-born American psychologist known for his pioneering work in experimental psychology, psychophysics, and optical illusions. He notably contributed to the field through his research on various optical illusions, including the famous Jastrow illusion. Jastrow believed that many people held misconceptions about psychology, and he dedicated himself to using the scientific method to clarify truths and educate the public. He achieved this through speaking engagements, writing for popular media, and appearing on radio broadcasts, aiming to bridge the gap between scientific research and public understanding. His contributions continue to influence psychology, particularly in the study of perception and cognitive processes.

Biography

Jastrow (1863–1944) was born in Warsaw, Poland. Joseph Jastrow immigrated to Philadelphia, USA, in 1866. He obtained his bachelor's and master's degrees from the University of Pennsylvania before pursuing doctoral studies at Johns Hopkins University. There, he collaborated with C. S. Peirce on pioneering experiments in psychophysics, focusing on randomized and blinded designs for repeated measures.

Jastrow's career flourished at the University of Wisconsin–Madison, where he served as a professor from 1888 until his retirement in 1927. He mentored notable psychologists like Clark L. Hull during his tenure. A founding member of the American Psychological Association (APA), Jastrow became its president in 1900. He was deeply committed to public outreach, delivering public lectures and writing for popular magazines such as Popular Science and Harper's Monthly. His syndicated column, "Keeping Mentally Fit," appeared in 150 newspapers, and he also gave radio talks from 1935 to 1938, broadening the reach of psychological knowledge.

Despite his professional success, Jastrow battled bouts of depression throughout his life. He passed away in Stockbridge, Massachusetts. His wife, Rachel Szold, was the sister of Henrietta Szold, and his cousin was the classical archaeologist Elisabeth Jastrow. His former residence in Madison, Wisconsin, is now part of the Langdon Street Historic District.

Contributions to Psychology

Psychical Research

Joseph Jastrow was involved in the American Society for Psychical Research, which studied mesmeric, psychical, and spiritual phenomena. Initially skeptical, he advocated for a psychological approach to these topics and criticized their separation from natural contexts. By 1890, he left the society due to his skepticism of parapsychology, believing that the researchers lacked credibility and evidence. In his book The Psychology of Conviction (1918), he exposed what he considered to be tricks performed by Eusapia Palladino.

Anomalistic Psychology

Joseph Jastrow was a leading figure in anomalistic psychology, a field focused on studying paranormal beliefs. In his book Fact and Fable in Psychology (1900), he rigorously debunked claims of occultism like Spiritualism, Theosophy, and Christian Science, approaching these topics with a scientific perspective. Jastrow aimed to understand why people were attracted to these beliefs, how they became popular, and the evidence used to support them. He critiqued paranormal phenomena as devoid of scientific basis, attributing belief in them to delusion, fraud, gullibility, and irrational thinking. Jastrow emphasized the scientist's role in helping the public distinguish between truth and fiction and combatting the spread of erroneous beliefs.

Use of Analogy in Society

Jastrow observed that analogies are a primitive method of interpreting the world. He cited examples from different cultures, such as the Zulu chewing wood to soften hearts and Illinois Indians making figures to shorten lives. He noted that such practices persisted through superstitions, rituals, and folk medicine, driven by a belief in interconnectedness.

Optical Illusions

Interested in perception, Jastrow believed eyesight was more complex than a camera. He studied optical illusions like the rabbit-duck illusion, illustrating how perception could change based on emotional state and surroundings.

Involuntary Movement

Jastrow invented the automagraph to detect unconscious hand movements. He found that when people concentrated on an object, their hand would move unconsciously toward it, with varying effects across individuals and more randomness in children.

Studying people who lost their sight, Jastrow discovered that those blinded after age six could still see in their dreams, while those blinded before age five could not. He concluded that sight isn't innate and that significant mental development occurs between ages five and seven. He highlighted hearing as the primary sense for the blind, both awake and in dreams, gathering insights from individuals like Helen Keller.

Jastrow Illusion

The Jastrow illusion, named after the psychologist Joseph Jastrow, is a visual phenomenon where two seemingly identical shapes appear to be of different sizes. Specifically, in the case of the Jastrow illusion, it typically involves two curved figures, often resembling arcs or segments of a circle. Despite their identical dimensions, one of these figures appears larger than the other to the observer's eye.

This illusion is commonly illustrated using figures like arcs or segments arranged in such a way that one end of one arc or segment overlaps with the other, creating a visual comparison. Even when measurements confirm that both shapes are indeed the same size, our perception tends to interpret one as larger than the other.

Several theories attempt to explain the Jastrow illusion. One theory suggests that our brain's interpretation of the two-dimensional image on the retina is influenced by depth perception cues, leading to a distorted perception of size. Another theory proposes that our attention and focus on different parts of the shapes might contribute to the illusion. Additionally, the contrast between the lengths of the arcs or segments may play a role in how our brain interprets their sizes, causing one to appear larger due to relative contrast effects.

The Jastrow illusion is not only intriguing for its visual impact but also significant in understanding how our perception and cognition interact. It underscores the complexities of visual processing and challenges our intuitive understanding of visual comparison. Despite ongoing research and multiple explanations, the exact mechanism behind why we perceive the Jastrow illusion remains a subject of continued study and debate in the field of psychology.

Criticisms of Psychoanalysis and Freud

Joseph Jastrow criticized psychoanalysis and Sigmund Freud's theories as unscientific and pseudoscience as early as 1913 during the German Psychiatric Association congress in Breslau. In 1932, he published a book titled The House that Freud Built further elaborating on his criticisms.

Works

On Small Differences in Sensation (1885) - Co-authored with Charles Sanders Peirce, published in Memoirs of the National Academy of Sciences, discussing minute differences in sensation.
The Time-Relations of Mental Phenomena (1890) - Explores the temporal aspects of mental processes.
Epitomes of Three Sciences: Comparative Philology, Psychology, and Old Testament History (1890) - Co-authored with Hermann Oldenberg and Carl Heinrich Cornill, providing summaries of these disciplines.
Fact and Fable in Psychology (1900) - Critically examines claims of occultism and pseudoscience in psychology.
The Subconscious (1906) - Discusses the concept of the subconscious mind.
The Qualities of Men: An Essay in Appreciation (1910) - Explores human qualities from an appreciative perspective.
Character and Temperament (1915) - Focuses on character traits and personality.
Charles Peirce as a Teacher (1916) - Published in The Journal of Philosophy, Psychology, and Scientific Methods, reflecting on Peirce's teaching methods.
The Psychology of Conviction: A Study of Beliefs and Attitudes (1918) - Analyzes how beliefs and attitudes are formed and maintained.
The House that Freud Built (1932) - Critiques psychoanalysis and Sigmund Freud's theories.
Wish and Wisdom: Episodes in the Vagaries of Belief (1932) - Explores various beliefs and their implications.
Story of Human Error (1936) - Discusses errors in human judgment and decision-making.

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