Remember when it was published that Pluto is no longer considered a planet? I remember that our physics teacher was really angry that the space agency was discarding something that was known and generally accepted by the general public. In my essay I will discuss how “old” knowledge was affected when new aspects of a particular knowledge were discovered. I will focus on two areas of knowledge: the natural sciences and the arts, and I will ask: to what extent can new knowledge contribute to the abundance of old and generally recognized facts? Today's medicine perfectly understands how human blood circulation works. However in ancient Greece it was believed that blood was linked to air, spring and cheerful personality, it was also believed that the liver produced all the blood. This belief was valid until William Harvey described blood circulation in much the same way we know it today. He added the crucial experimental discovery that blood is "pumped" around the body by the heart. This foundation caused a chain reaction in medicine. New discoveries were discovered that led to our current understanding of medicine as we know it today. If you asked a random person how the Greeks thought about blood circulation, only a few could answer this question correctly because this “old” knowledge was discarded as soon as a new discovery appeared. That discovery caused a paradigm shift in the natural sciences. Not only in medicine but also in biology, chemistry and physics and this is basically what paradigm shifts are about. Some paradigms are a general theory shared by the community of scientists, which is used to make sense of some aspect of reality. A scientific revolution or paradigm shift occurs when scientists become… middle of paper… prior knowledge critically to decide whether that knowledge is really worth the abundance. Fortunately there are some scientists who later discover that discarded knowledge and take it as the basis for their further research (as in the Leibniz–Einstein case) which helps to establish new aspects of knowledge. Works Cited • Wikipedia. "Blood." 2014. http://en.wikipedia.org/wiki/Blood#History (accessed 2 February 2014). • Planetseed.com. "Medicine and the scientific revolution | History of medicine | PlanetSEED." 2014. http://www.planetseed.com/parentarticle/rise-scientific-medicine-scientific-revolution (accessed 2 February 2014).• Lagemaat, Richard Van De. Theory of knowledge for the IB Diploma. Cambridge: Cambridge University Press, 2005.• Wikipedia. "Cinema". 2014. http://en.wikipedia.org/wiki/Movie_theater#Splling_and_alternative_terms (accessed 2 February 2014).