Could you show us how this works? For example, when would you say that the first biological life forms - self-replicating molecules - first appeared on earth?
Excellent question.
I would begin by asking questions. Is this a repeatable event? No it is not. Can I go back in time to see the first biological life form, no I can not. I then ask, does this mean I have no way of knowing beyond a reasonable doubt how the first biological life came to be? I answer, no it does not.
I then ask can this occurance be repeated in a laboratory, no it cannot.
From there I would ask, what are the prevailing contemporary views from the experts in this matter. I gather all prevailing views and collect them under two broad explanatory categories: The naturalistic explanation(s), and the supernaturalistic explanation(s).
From there I examine each with objective critical thinking and assimilate the findings of the experts in their respective fields using a variety of means and methods which are pertinent to the evidence being examined. I examine the origins of the naturalistic framework, I examine the origins of the supernaturalistic framework. I make use of the inductive method and the cartesian, as well as the forensic science method with its principle of uniformity.
I examine the claims of each and understand that opposing truth claims cannot both be true. Either naturalism is that framework which best corresponds to reality, or either supernaturalism is. I start with certain unshakable presuppositions and build my case from there. I presuppose the intelligibility of the world around me and that it can be known.
The specific question is when did the first biological life forms appear on earth.
This question is hotly contested by many who are engaged in seeking to find a reasonable answer and I know before I even set out to find an answer, that if I do indeed find one that is widely accepted, it is not going to be an exact date, I dont expect it to be. I first begin by going to my computer and typing in: "when did the first biological life forms appear".
Simple huh? Hahah
In several milliseconds have a vast treasure trove of information that needs to be sorted and compiled. Boom! Wikipedia comes up with an article on:
Timeline of evolutionary history of life - Wikipedia, the free encyclopedia
Under the basic timeline heading it states:
The basic timeline of a
4.6 billion year old Earth, with approximate dates:
And so on and so forth.....
I then scroll down and see:
3900 Ma
Late Heavy Bombardment: peak rate of
impact events upon the inner planets by meteoroids. This constant
disturbance may have obliterated any life that had evolved to that point, or possibly not, as some early
microbes could have survived in
hydrothermal vents below the Earth's surface;
[12] or life might have been
transported to Earth by a meteoroid.
[13]3900-2500 Ma
Cells resembling
prokaryotes appear.
[14] These first organisms are
chemoautotrophs: they use
carbon dioxide as a
carbon source and
oxidize inorganic materials to extract energy. Later, prokaryotes evolve
glycolysis, a set of chemical reactions that free the energy of organic molecules such as
glucose and store it in the chemical bonds of
ATP. Glycolysis (and ATP) continue to be used in almost all organisms, unchanged, to this day.
[15][16]
I say to myself, hmm ok...I have a rough foundation I can work on and build from here. I then check every source for credibility. I then examine any other prevailing views concerning the above dates and see how they agree or diverge. I by no means take the Wikipedia article to be conclusive. We all know why, but it is a good place to start. I assimilate the prevailing naturalistic views as well as the prevailing supernatural views. And see where they agree and where they diverge. I then ask, why the divergence if any, and then examine each side's case. I examine all prevailing origin of life hypotheses, theories, and explanations for consistency, internal coherence, and correspondence. I examine all related subjects such as the varying age of the earth views, etc. etc.
In sum,
Utilizing the information at my disposal, (much is still contested with regards to the origin of life research) I can come to a reasonable conclusion that among those who fall under the naturalistic category, they believe life began approximately 3 billion years ago give or take a billion. Among those who comprise the supernaturalistic camp, views differ accordning primarily to one's view of the age of the earth.
The above once taken into consideration leads to an even more profound question. Not so much as when it occured, but
how it occured, and even more profoundly, entering into the philosophical disciplines,
why? For even if a general consensus is reached on when, we must ask
how and
why life exists. These two questions are the motivation for most of the work going on in contemporary scholarship with regards to the origins of life and it should be our aim to ask the
most important questions.
In addition to the above, one must ask, what is the relevance of the question I am asking? How does knowing the approximate time in which life arose on earth affect me? Many pursuits for knowledge on various subjects have been undertaken with zeal by men and women alike only later to be abandoned for something
more important. This is a question we all must ask and answer ourselves.