Zephan: What is Evidence?

Percipient gave this definition of evidence: So far you've yet to address this definition. I suspect it may be because it didn't come from Mark himself. However I suspect he agrees with it (although I won't speak for him.)So maybe you could address this definition and outline where you feel it's wanting? Because the evidence in support of evolutionary models is all stuff that you can see yourself, given knowlege of the procedures for it's discovery (i.e. how to use a microscope, etc.) Taken together, the evidence is overwhelimingly in favor of evolutionary models as explanations for the diversity of life on Earth. But no one experiment or observation is going to provide incontrovertable "proof" of the evolutionary model, if that's what you're after. But science isn't done that way, as far as I understand.I don't see why this definition wouldn't be good enough for you. it's good enough for people who do science, which in turn is good enough for people to apply to practical use (technology).------------------
Epimenedes Signature: This is not a signature.[This message has been edited by crashfrog, 03-29-2003]

A post or two from zephan and yet he appears to ignore the definitions of science that posters have presented.As off-topic as it may be, I'm going to go ahead and predict that he will ignore Percipient's and Schrafinator's separate but similar definitions (data avaliable to our five senses).ZEPHAN: I'm accusing you of ignoring direct answers to your demand for definitions, and then continuing to demand as though you've recieved no answer. This is a clear falsehood. Maybe you'd like to address this? Prove me wrong.------------------
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Why would it be meaningless? the scope of science is limited only by what can be observed and tested. Then theories are made to explain those observations and tests. Often the theories make predictions; later these can (or caannot) be born out by further observation or test. (The progress of technology expands our ability to make observations we couldn't before, by expanding the reach of our senses.)In that sense, everyting IS evidence in one way or another. However, some evidence is unrelated to the hypothesis in question (for instance, the temperature in brazil is generally unrelated to the question "Is light a wave, a particle, or both?") and thus is not considered. How do you tell if the evidence is relevant? Generally it's trivial to distingush, because your hypothesis will be phrased in such a way as to suggest what evidence will be relevant to it. For instance if I hypothesize that adding sugar to tea will make it taste sweet, tasting the tea will be relevant evidence. The color of the teapot will not be relevant.Note that evidence is never rejected because it contradicts the hypothesis (peer review exists to ensure this is discouraged), but evidence may be rejected because it has no bearing whatsoever on the hypothesis.Why do you think that the definition of evidence would be found in a peer-reviewed journal? I think we've addressed that. What you may be asking is "What constitutes relevant evidence for any particular scientific hypothesis?" There isn't really a hard and fast rule, and in fact that's what most of the debate among scientists on any given issue is about - whether the evidence they cited is relevant to the hypothesis and if the evidence supports the conclusion. Sometimes the same evidence can support multiple conclusions. In cases such as this, the issue is decided often by the weight of evidence.The more I think about it, the more I think you're asking "what constitutes relevant evidence to any given hypothesis?" Maybe that's helpful to the other people trying to explain. If this isn't your question please say so.------------------
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It seems pretty obvious to me that "bias" and "motive" aren't at all evidence, but rather conclusions that would be inferred from evidence. i.e. "the suspect was the beneficiary of the victim's life insurance (verifiable observation - evidence). thus we infer a motive for the murder (conclusion based on evidence)."Wow, if you think conclusions are evidence, and you can't tell the difference between abstract concepts and concrete observations, I wouldn't want you as my lawyer... I mean (according to tv) evidence is labeled and presented to the baliff - where would you stick the label on "motive"? But I'm no lawyer so I'm sure you can explain why I'm wrong.------------------
Epimenedes Signature: This is not a signature.[This message has been edited by crashfrog, 04-01-2003]

Well, of course I do not believe everything I see on tv. I merely mentioned that sadly, my only experience with courtroom procedings comes from watching Perry Mason. I specifically mention this to avoid being mistaken for any kind of legal authority.I'm not sure that testimonial evidence can be equated with the peer-reviewed journaling process. I think it is better to equate that with a jury (of one's peers, right?). A scientist, trying to argue a certain hypothesis, presents a description of his experiments, their results, field observations he may have made, etc. and then attempts to construct a conclusion that explains this data. The "peer-review" process means that when his article is published, other interested scientists in the same field compare his observations with theirs, perform the same experiments under similar conditions, and basically try to establish the replicatability of his data. Then they may accept his conclusions, or construct their own to explain the data.If the experiments can't be successfully repeated (as was the case in the famous cold fusion hoax), then the scientist's conclusion in called into question, and generally rejected by the scientific community.In science, testimony is simply another kind of physical evidence. An individuals testimony can be recorded to demonstrate to other scientists. But one testimony is not enough to construct conclusions or support a hypothesis. Many, many such testimonies are required. With these, you could begin to construct a hypothesis such as "Humans under the age of 16 believe in the tooth fairy." Note that you could not support a hypothesis of "there is a tooth fairy" with this data. That would require actual physical observation or evidence of such a fairy. Similarly, eyewtiness testimony of the comission of a murder proves nothing without independant evidence of such a murder happening - like, a dead body, a murder weapon, etc.As for relavant evidence for evolution, that would be any evidence that was related to living things on this planet. Not just evidence relevant to organisms evolving, but the total evidence from all living things (remains/fossils, genetic data about heredity, population studies, etc). Scientists do not only consider data that they think will support their hypothesis. Such a scientist would be instantly discredited. Scientists must consider all data at all relevant to their hypothesis. Sometimes scientists argue about what data is and is not relevant (and they must support their positions when they do). Objections that scientists are considering data only in support of evolution to the exlusion of other relevant data are false, because no scientist in any field could get away with that. The peer-review process ensures that scientists must consider all relevant data for and against their hypothesis. In fact they must specifically state what kind of evidence could disprove their hypothesis when they form it. This is called "falsifiability" and involves constructing the "null hypothesis", which is the term for the data that would disprove the orignial hypothesis. The job of the scientist then is to argue that the null hypothesis is unsupported by the data, which would lead to a confirmation of his original hypothesis.In the case of evolution, one of many null hypotheses could be "characteristics of organisms can never be inherited by their offspring" or "in populations of organisms, all organisms have an equal chance of surviving to procreate." Both of these null hypotheses can be rejected because we observe data contrary to them. Another such hypothesis would be "the fossil record does not show gradual change in organisms over the history of life." Again, we reject this hypothesis because we have data that does in fact suggest that over time, organisms change.So to disprove evolution, you have to start by providing a better explanation for the data that is contrary to the null hypotheses that I've outlined (as well as a host of other, more specific ones.) Then you have to find data to confirm these null hypotheses. In order to prove creation you would have to provide hypotheses, construct falsifiable nulls, and then find data to reject those nulls. That none have ever been able to do so is telling.I'm hoping this helps convince you that all science (even evolution) is conducted within a general methodology that has been supported for 200 or so years simply because it's really good at getting the most accurate results possible (within the constraints of avaliable data). I don't think the same can be said for the legal system, unfortunately, which has to work under significant constraints of time, manpower, and a certain bias towards the accused (innocent until proven guilty is a kind of research bias that would not be accepted in scientific literature).------------------
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