hi this is Harry this is the first in a four-part series answering the question what is science so we'll be using the items of the nature of science quiz developed by Larry flamer so make sure you've done that quiz before you start watching this film so what is science and where did science come from the word itself comes from the Latin senta which means knowledge so whilst Aristotle defined science as the body of reliable knowledge itself of the type that can be logically and rationally explained the modern def definition is slightly different so to Aristotle science was any reliable knowledge and it didn't matter how it was derived in fact Aristotle used logic and reasoning as his main tools back then science and philosophy two quite distinct Fields today are used interchangeably over the 19th century science became increasingly associated with the scientific method and experimentation became a key defining element and this is the definition that we'll be adopting so today we'll Define science as the process by which knowledge about the natural universe is gained and seeks to move towards a more accurate precise and in-depth understanding of the universe and the stuff in it so let's begin by looking at these five items of the natural science quiz so while certainly science has given us the airplane the iPhone antibiotics modern agriculture great telescopes satellites and cars the primary purpose of science is actually to develop knowledge which is durable with ever increasing comprehensiveness precision and certainty so you can essentially say that science is the search for truth however this definition is problematic for some the revealed truth of God or other deity or authority is considered to be absolute final and always correct regard less of observations or study that may suggest alternative explanations so this point raises important questions about scientific knowledge and how it differs from other types of knowledge scientific knowledge is never considered to be absolute final or always correct it can always be overturned by new discoveries so in this sense scientific knowledge is always considered to be tentative so for example Aristotle and Tommy both believed that the Earth was the center of the univers ver and use epicycles and even more complicated epicycles to explain the motion of their Heavenly Bodies such was the reputation of Aristotle and toomy this view held sway for almost 2,000 years and no one challenged them as an aside a suncenter model was Pro proposed by arist aristas of Samos around 200 BC but that's beside the point it wasn't until the 16th century did polish astronomer cernus propos that the sun was at the center of the universe with the planets orbiting in perfect circles this was close but not quite correct building upon kernus idea Kepler using another famous astronomer's data Tao brahi went on to propose his three laws of planetary motion one of which is that all the plants orbited in ellipses and this made the Sun the focus of one of those ellipses crucial evidence for the cernic model of the solar system was provided by Galileo and later built upon by new who demonstrated the laws that govern the heavens also govern the motion of the objects on Earth the rules that apply in outer space also apply here on Earth and everywhere else in the universe so in terms of astronomy durable scientific knowledge could be considered that the sun orbits the Sun in ellipses The sun is one of billions of stars in the in the Milky Way and the Milky Way is one of hundreds of billions in the the universe so the take-home message from this section is that science is concerned with the understanding reality and as a con consequence generates knowledge and leads to invention of new devices that the authority of the person doesn't matter it's what the knowledge says the science is self-correcting that wrong ideas are eventually discarded for more information you can look up the development of the atomic theory scientific knowledge applies everywhere in the universe at all scales and for all times that scientific knowledge has universality and that scientific knowledge is cumulative and seeks to be more comprehensive more accurate and more precise over time and here's a message from Professor Steven Hawking