Evidence is a thing or things that help in attaining knowledge. The statement “that which can be asserted without evidence can be dismissed without evidence” means that it is possible to confirm and dismiss the same if there is no evidence or proof to form an undebatable judgement. In this essay I am going to analyse this quote from the prospective of different Areas of Knowledge. I will proceed in this way because they differ from each other not only in the branch of human knowledge that they cover, but also in the Ways of Knowing used to gain the evidence on which each Area of Knowledge is based. My argument will agree with the statement discussed in most Areas of Knowledge, however it will also notice that the statement cannot be applied in particular
Areas of Knowledge.
“A wise man,” wrote Hume, “proportions his belief to the evidence.” What the british humanist said with this quote was that what human belief is very closely related to the evidence thay have as men can believe the truth of a statement only if this is based upon evidence. Therefore, if we consider Hume’s point, the quote “that which can be asserted without evidence can be dismissed without evidence” is not heavily relevant to knowledge as nothing wise men believe and assume should be based without evidence.
The first Area of Knowliedge I will consider is the one of Natural and Human Sciences. These are branches of human knowledge which are based upon the scientific method. Therefore, in Sciences knowledge is asserted (and dismissed) using concrete empirical evidence . Assuming that this is always the case, in theory the quote that I am analysing would therefore not have a real meaning and context and it would be impossible to agree or disagree with it. In the history of scientific discovery however, we can identify some examples of scientific claims that were disserted by furter studies, but often the falseness of the first claim was due to limitations of the scientific method at the time it was first asserted.
An example could be the geocentric model in astronomy by the Greek scientist Ptolemy that placed the earth as the orbital centre of all celestial bodies. This theory was believed to be true for 1500 years until in the 16th century the heliocentric theory was presented by Galileo Galilei. This theory replaced the previous theory and was based on the proof that the movement of celestial bodies around the earth was an apparent movement caused by the human parallax error and that places the Sun as the centre of all celestial bodies.
Regarding Natural Sciences, a well-known example of a claim based upon the scientific method is Mendel’s law of indepenndent assortement, that I could analyse in the IB Biology course. This theory states that “two or more pairs of alleles segregate independently of each other as a result of meiosis, provided the genes concerned are not linked by being on the same chromosome” and the scientist could make this claim on the base of an observation followed by thousands of experiments on genetics that allowed him to build an hypothesis that was then tested and approved by humanity to be a scientific theory.
This type of reasoning can also be applied with Human Sciences. For example, the discipline of Economics is fundamentally based upon reason and sense perception. These Ways of Knowing were used to obtain a few key definitions that contain reliable truth, such as the concept of scarcity in which we acknowledge that world resources are limited while human wants are unlimited. Although the subject is based on such concepts, it is apparent that when economists search for a theory or an answer in this field, there is often no other answer than “it depends”. An example of this ambiguity in macroeconomics is that related to the question: “How should a government improve its macroeconomic deficiencies (e.g. high unemployment or high inflation)?” There are two main schools that present this issue: the Keynesians argue in demand policies while New Classicals argue that supply management policies allow a long-term improvement in these deficiencies.
The question that arises from this reasoning is the following: “Is there then a “true” theory and a “false” one?” The answer is No, as both these contrasting theories are based upon reason and sense perception. However, to a degree they also dismiss the other theory. In fact, as the discussion is about which theory is best for governments to improve its macroeconomic deficiencies, there can be only one theory that respect this statement. Here again it is shown how a scientific claim based upon reason and sense perception is not necessarily true as it can be displaced by another theory based upon other evidence. Therefore, in this Area of Knowledge I agree with the statement “That which can be asserted without evidence can be dismissed without evidence”.
A key knowledge issue is the counter argument to the underlying assumption of the title. If one is to base an argument or a knowledge claim on the need to provide evidence, then one must also provide evidence to dismiss a competing argument. What this means is that in order to dismiss an assertion, one would indeed require evidence in order to prove the dismissal. The statement is therefore not entirely correct and the classical economics answer of “it depends” applies!
I will now move towards the Area of Knowledge of ethics. This Area of Knowledge is key in understanding the truth of the statement “that which can be asserted without evidence can be dismissed without evidence” that is being discussed because, differently from other Areas of Knowledge, its evidence is based mainly upon sense perception and emotion. An example of an ethic issue that could help me to understand whether to agree or disagree with the statement debated is the recent hoax call to the Duchess of Cambridge’s nurse, which resulted with the suicide of the same nurse three days after the call was made.
The ethical issue in this case is whether to define this event as a tragedy, and therefore the hoax call as a resonable joke, or to define it as a contributory negligence of the DJs and the radio station involved. Ethics, unlike Mathematics and Sciences, is a very subjective Area of Knowledge as people evaluate situation with different parameters and in different ways. The answer to these questions is, again, it depends and this agrees with the statement “that which can be asserted without evidence can be dismissed without evidence”.
Taking now the last approach to this dissertation on the truth of the quote by Christopher Hitchens, I am going to relate it to the Area of Knowledge of Mathematics. This branch of human knowledge is possibly the most reliable one as it is based upon purely reason, which allow Mathematicians to claim mathematical poof, a formal series of statements showing that if one thing is true something else necessarily follows from it. An example of this is that, if we know that a triangle has all its angles of 45°, then all its side lengths will be the same.
However, all Mathematical claims come from a set of unprovable axiomes, that are claims so evident as to be accepted as true without controversy. An example of these is “a line is made of an infinite number of points”. These assumptions are logical and understandable to humans, but it does not mean that they are reliable evidence because it has still not been possible to give concrete empirical evidence that support these claims. Does this mean that Mathematics is not based upon evidence? Can Mathematic proofs be disclaimed in the same way as they were asserted?
The answer, from my perspective is no to both questions because Mathematics and Physics are foundations for human knowledge, and the human environment itself gives us the evidence that Mathematics and Physics are based upon evidence. For example, the building of a skyskraper and the flying of a plane could not happen if physics was not based upon evididence given by reason.
After analysing the statement “that which can be asserted without evidence can be dismissed without evidence” in four different Areas of Knowledge, I came to the conclusion that I agree with the statement in the cases of Natural and Social sciences, but I disagree on the validity of this statement regarding Ethics and Mathematics. The reason why my judgement is different regarding different Areas of Knowledge is in the “nature” of these, as the evidence used to support them is gained from different Ways of Knowing.
 Biology for the IB Diploma,C.J.Clegg, Hodder Educaton, page336  Gregor Mendel, Father of Genetics http://www.detectingdesign.com/gregormendel.html  http://www.guardian.co.uk/uk/2012/dec/07/duchess-cambridge-hoax-call-nurse-found-dead  http://www.thefreedictionary.com/Proof+(math)
 Principia Matematica Vol. 1, A.N.Witheread and B. Russell, Cambridge University Press, 1963  http://library.thinkquest.org/2647/geometry/intro/lp.htm