“There are only three states of matter: solid, liquid, gas.”

The idea that matter exists in only three forms—solid, liquid, and gas—is a deeply ingrained misconception, largely because these are the states most commonly encountered and easily observed in our daily lives. Historically, the distinct properties of solids, liquids, and gases were well understood and became a standard part of scientific education by the mid-19th century, serving as fundamental concepts for understanding the physical world. This foundational teaching, focusing on what is readily apparent, inadvertently cemented the belief that these three were the *only* states.

However, scientific discovery has long since expanded this view. Plasma, often referred to as the fourth state of matter, was first identified by Sir William Crookes in 1879, who called it "radiant matter." Its true nature, an ionized gas where electrons are stripped from atoms, was later clarified by J.J. Thomson, and the term "plasma" was coined by Irving Langmuir in 1928. While less common on Earth's surface, plasma is the most abundant state of matter in the observable universe, making up stars and much of interstellar (Review) space.

Beyond plasma, scientists have discovered and created numerous other states under extreme conditions. These include Bose-Einstein condensates (BECs), first predicted by Satyendra Nath Bose and Albert Einstein in the 1920s and experimentally realized in laboratories in 1995 when atoms were cooled to fractions of a degree above absolute zero. Other exotic states like fermionic condensates and superfluids also exist. The common belief in only three states persists because these more exotic forms of matter typically require conditions of extreme temperature or pressure that are not naturally present in our everyday environment, making them less intuitive and less frequently taught in introductory science.