Phrenology is one of those creepy and antediluvian pseudo-sciences responsible for much racket in the 19th century but which is now doomed to the dustbin of failed scientific hooey.

According to Britannica, phrenology is the study of cranial physique as indicative of mental capacity and character quality. In other words, the shape and size of the skull can determine character and intelligence. Franz Joseph Gall is said to have founded the discipline upon the following hypotheses: 1) the brain is the organ of the mind. 2) the mind is composed of various distinct, innate faculties. 3) because they are distinct, each faculty has a separate region in the brain. 4) all else being equal, the size of an organ is a measure of its power. 5) the shape of the brain corresponds to the development of its various regions. 6) the shape of the skull corresponds to the shape of the brain, and thus can be read accurately as an index of psychological aptitude and proclivity.

The fragility of these hypotheses, however, is stunning. For one, the notion that the skull can be read as a calcified map of the brain is absurd on its face (or, should I say, on its head). Also, that the size of an organ is a measure of its power is a little ridiculous because---ah, well, just because.

Nevertheless, what these hypotheses imply is that a qualified phrenologist---which means about as much as a qualified palm-reader---can look at your noggin and deduce who you are as a person and who you might become. Indeed, according to the Victorian Web, back in the phrenological hoo-ha of the early 19th century, employers could require a character reference from the local phrenologist as guarantee of the prospective-employee’s abilities and personality.  

For example, many phrenologists believed that a prominent outgrowth of the forehead evinced benevolence of character. Soon, however, it became apparent that people with small foreheads could be benevolent too, and that some of our bigger-headed brethren could be quite cruel and nasty.

A more serious criticism of phrenology is that it laid the methodological groundwork for its crackpot cousin, craniometry, which was deployed to justify racist cartoons of African-Americans as intellectually inferior due to the measurements of their skulls.

Thus, after making a sizeable ruckus, phrenology soon retreated to the philosophical fringe from whence it came. Although, I must say, those with the smallest minds and biggest heads do always seem to have certain somethings in common.

Sources:

Britannica, The Editors of Encyclopaedia. Phrenology. Encyclopaedia Britannica, Encyclopaedia Britannica, Inc., 1 May 2018, www.britannica.com/topic/phrenology.

Wyhe, John van. The History of Phrenology. The History of Phrenology, 2000, www.victorianweb.org/science/phrenology/intro.html.