One netfriend wrote: [snip] It is true that Evolution is not about the origin of life. Evolutionary scientists do not emphasise that as they can't prove it. But they do say that once life began that evolution occurred up 'a tree of life'of one life form evolving into another without scientific proof.

Chris responded:

Actually, we most certainly do have a scientific proof for the evolutionary development of the tree of life.

A scientific proof means an inference from empirical evidence, confirmed to the point where it becomes perverse to withhold provisional consent. This definition of "fact" comes from Gould:

Moreover, "fact" does not mean "absolute certainty." The final proofs of logic and mathematics flow deductively from stated premises and achieve certainty only because they are not about the empirical world. Evolutionists make no claim for perpetual truth, though creationists often do (and then attack us for a style of argument that they themselves favor). In science, "fact" can only mean "confirmed to such a degree that it would be perverse to withhold provisional assent." I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms. -- S.J.Gould, in "Evolution as Fact and Theory" Discoverse Magazine, May 1981. <http://www.stephenjaygould.org/library/gould_fact-and-theory.html>

A decent science education should let students be aware of the nature of "proof" and "fact" in science. There is a good explanation available here: "Scientific Proof?" by Douglas Theobald <http://www.talkorigins.org/faqs/comdesc/sciproof.html>

So far; all I have presented in this post is a definition of terms.

The more difficult question is whether or not evolution really is confirmed and supported to such an extent.

To judge that, one needs to be aware of the available evidence; and to follow that in detail is an difficult and time consuming undertaking. The amount of evidence is enormous; and it comes in many forms relating to many different scientific fields. But to make the judgement as to whether a scientific hypothesis (like the evolutionary tree of life) should be considered proved in the scientific sense; this is what is required.

The scientific community has long since made that judgement, in no uncertain terms. And a good education in science should also gives students an appreciation not simply of scientific conclusions, but of their evidential foundation; the *reasons* why they are considered conclusions.

In fact, evolution stands in relation to biology in much the same was as the periodic table stands in relation to chemistry. It is the fundamental explanatory model which makes the whole field of study into a coherent whole. It is as solidly confirmed by evidence as almost any other scientific model you care to mention. The sheer volume of information accumulated over the last century has long since meant that the phenomenon of evolution-denial is exclusively based on either ignorance or irrationality: invariably associated with poorly thought out religious views.

A list of some of the available evidence confirming evolutionary biology can be found here: "29+ Evidences for Macroevolution The Scientific Case for Common Descent" by Douglas Theobald, <http://www.talkorigins.org/faqs/comdesc/>

There are many other resources at the same site which set out more lines of evidence as well.

Cheers -- Chris