In answering the question asked in the subject of this thread it’s important firstly to define, ‘Atheism’. It’s most common definition seems to be similar to the following:
Atheism – a lack of belief in god(s)
Whilst I’m aware of other (and in my view better definitions of atheism) I want to restrict this thread to atheism as so defined and to give my answer to the question as being in the negative, i.e. it is not a tenable position to hold.
The reasoning behind my answer is as follows:
Whilst ‘a lack of belief in god(s)’ is the commonly given definition of atheism, it’s just as common, if not always the case, that upon being asked the basis of this lack of belief atheists will reply that it is based on the absence of evidence to warrant belief. It is on that basis that I consider atheism to fail for there is no such absence of evidence but many lines of evidence that a god or gods exist. But what are those lines of evidence? I present them as being every rational argument presented that tends to prove a god or gods exist. Such arguments are commonly known, but usually just as commonly dismissed by the very same atheists proclaiming an absence of evidence and are:
1. Cosmological Arguments
2. Teleological Arguments
3. Ontological Arguments
4. Arguments from Objective Morality
5. Arguments from the Bible
6. Arguments from Miracles
7. Arguments from Personal Experience
Now it can be immediately granted that of these arguments some are far from convincing on their own (3, 6 and 7), but as part of a cumulative argument with those following from previously established conclusions they also can be valid (e.g. the argument from the Bible is stronger when based upon the establishment that a god (generic) exists than it would do without such a basis).
Where that leaves us with various presented rational arguments for the existence of god(s), any one of which is true or probably true or, taken together as one cumulative argument were true, would falsify the claim from the atheist of an absence of evidence for god that justifies their lack of belief.
On this it seems to me that the only way an atheist could justifiably hold to this atheism would be to counter each and every argument (line of evidence) that is proposed in those arguments, either individualistically or as a cumulative argument. If that were done then of course the atheist view is justified because lines of evidences presented to them have been countered and shown as false trails to evidence but, in my experience, few atheists have taken on this task, or are prepared to take on this task when the evidence is presented.
On that basis I propose that this atheism is not a tenable position to hold for any atheist presented with those arguments who refuses to consider them or fails to rebut/refute them.