For Science!5 Obsolete Theories That Scientists Once Widely AcceptedFor Science! - RSS 2.0
Once upon a time, scientists actually believed the world was flat, the center of the universe, and composed of four elements. These were not views held by crackpot theorists living on the fringes of society - reputable scholars representing the scientific community held these beliefs. That is, until radical thinkers brought to light new evidence to cause paradigm shifts that would evolve our understanding of the world we inhabit.
Here are five other obsolete theories once commonly accepted by mainstream science.
1. Emission Theory
How do we see? Our brains process the information held within visible light, which either issues directly from a source or is reflected off objects and "bounced" into our eyes. According to emission theory, our eyes aren't receiving these rays of light - they are emitting them. In short, we see by shooting "sight" beams from our eyes.
Emission theory was first proposed in the fifth century BCE and supported by the likes of renowned scholars Plato, Euclid and Ptolemy. However, there was always a school of thought that opposed this notion and supported ideas more in line with our modern understanding of vision - though that understanding may not be as widespread as the education system would hope. A study conducted in 2002 found that as many as 50% of American college students believe human vision operates on principles in line with emission theory.
Curiously, ray tracing technology in computer graphics is a technique that generates images in a manner very similar to emission theory, by tracing a straight-line path from the camera (or eye) to the objects in front of it and gathering the information needed to construct a picture.