The World is Flat – The "None", the "Non-", the Non-Theist:
[Version 6-01-17] On the term Atheist and its definition, the report of “a lack of evidence” is fairly accurate on the more common definitions in general. Interestingly, what the word Atheism in fact referents has become so diversified and generalized that it has lost its ability to be helpful in any reliable fashion. A simple example: it has drifted so far afield that (some) Buddhists claim they are not "Atheists" because they are "spiritually minded".
Entire discussions on the utility and meaning of the term Atheist are not uncommon and for good reason. If one has a discussion as to why the term "Non-Theism" is of greater utility than the term "A-Theism" then one can certainly point out where such a discussion gets it wrong or gets it right, but the discussion itself is always illuminating.
Regarding the "None", the "Non-", the Non-Theist...... and why it is a superior term to "A-" (Atheist) etc. with respect to precision as to what one actually does affirm, that carries over into the fallacious nature of the claim about one's own belief-state in the statement, ".....my claim of Not-Your-God is "nothing-but" non-belief...." which our Non-Theist friends so often claim.
That's why "Non-Theist" is more precise as it speaks not to a person's (an atheist's) self-report of insufficient evidence but rather it speaks to his actual belief-state, to what he affirms, to what he in fact likes, to what he gives intellectual assent to, and, thereby, to what every possible metaphysic available to him necessarily lacks within its own frame.
That brings us to the following three forms of what is in fact one common claim:
 “One God further than you…”
 “One less God than you….”
 “One fewer Gods/gods than you…”
If you are not familiar with it, an introduction can be found in a discussion of the One God Further Objection. Also, fundamental flaws in the “One Fewer Gods / One Less God / One God Further” line of reasoning are briefly looked at in the comments  Part 1 http://disq.us/p/1gxarix and  Part 2 http://disq.us/p/1h06j3a (...depending on browser variables links to specific comments may take a few seconds to open...)
Whether or not the "Non-" specifically claims and/or dives into Panpsychism, Idealism, Buddhism, Naturalism, Materialism, Immaterialism, and so on does not change the fact that the Non  has his respective explanatory terminus and  said terminus *is* one's respective irreducible substratum from which all definitions necessarily stream and  at some ontological seam somewhere one's claims upon the fundamental nature of reality or of being will either trade away or else land within the Necessary, the Immutable, the Irreducible, the Self-Explanatory (....contra the Contingent, the Mutable, the Reducible, the Brute Fact...).
Nowhere does this press upon us more relentlessly than in the elemental and irreducible processions constituting Love and Logic, or Reciprocity and Reason. Therein the "Non-" becomes manifestly infinite. Therein (any) one's metaphysical wellspring of all ontological possibility compels either closure or else insolvency.
The nature of the question here has significant overlap with the "One Fewer God" or “One Less God” challenge often foisted as a challenge against the Christian, or more precisely as a claim which the Non-Theist makes with respect to his own belief-state. The core of that is obviously fallacious given the fact that the doxastic experience is not – and cannot be – a vacuum void of belief and given the fact that all of our own upstream beliefs give life to all of our downstream claims upon what counts as rational inquiry and what counts as rational metrics. Therein everyone has his or her explanatory terminus:
"The reason is that for the classical theist, whatever else we mean by “God,” we certainly mean by that label to name the ultimate source, cause, or explanation of things. Properly to understand classical theism, the hostile atheist reader might even find it useful to put the word “God” out of his mind for the moment -- given all the irrelevant associations the word might lead him to read into the present discussion -- and just think instead of “the ultimate source of things.” (E. Feser)
The following is perhaps also helpful for context:
“Actually it is quite easy to reject atheism because atheism is the rejection of a certain conceptualization or definition of the term God. Monotheism in the Abrahamic tradition conceptualizes God as the one source of all that exists. To claim that all that exists has no source or cause is simply to deny reality, most particularly, to deny science itself. Atheists can’t have it both ways: to deny that there is an explanation through science for all that exists and to deny that what we monotheists give the name God to as the source of all that exists Himself/itself exists. Atheism is inherently illogical and inconsistent.” (by J.Black)
Description isn't explanation. Cosmology is not, and cannot "become", ontology just as physics is not, and cannot "become", ontology. The contours of the "Fallacy of Composition" press in even as the irreducible contours of "Being Itself" press in as the only contours which Non-Theism ultimately finds are those of “Brute Fact”. Finally, in the end, the syntax of “useful but not true” unmasks the illusory and the absurd at all "levels" of reality and – thereby – assumes ownership of all claim-making by all claim-makers.
None of this is about missing knowledge of physical systems. All of this is about what granting all knowledge of all physical systems does not and cannot even in principle grant to any Non-Theistic paradigm.
Non-Theists too often fail to realize just what "Brute Fact" necessarily forces upon all of their claim-making, which, of course, includes all slices of "reality" which we think of as the physical sciences. They mistake Brute Fact for "...we've not figured it out yet, and maybe we never will....", as in, they equate it with merely one more vector in a series of problems vis-à-vis gaps – and the God of Gaps fallacy typically comes roaring in there. It's a common error. The Non-Theist is guilty thereby of an argument which is itself based on GAP and not on logic, reason, sound metaphysics, and the testimony of physical systems – as irony emerges. What is needed instead is the knowledge of physical systems in the context of the ultimate self-explanatory principle, such as  http://edwardfeser.blogspot.com/2013/10/why-is-there-anything-at-all-its-simple.html and also  http://edwardfeser.blogspot.com/2016/02/parfit-on-brute-facts.html and also  http://edwardfeser.blogspot.com/2014/03/an-exchange-with-keith-parsons-part-iv.html begin to discuss.
With respect to our belief-states:
What misses the point with respect to the question on the table is the claim by Non-Theists that it does not matter if they do or do not have beliefs about reality’s ultimate source because either way they don’t think that “it” is “God/god”.
None of this is new information. We all have beliefs about reality which inform us on how best to inquire about reality. Beliefs about reality drive our modes of inquiry with respect to reality. According to some, this or that cousin of physicalism gives us the most exhaustive explanatory accounting of reality, while according to others that is hardly the case. Offshoots or products of that lead into conflations of the descriptive for the explanatory, and into the nature of brute facts and the nature of the self-explanatory, and into several other downstream consequences of those initial, upstream beliefs. If we claim we have no such beliefs, then we may want to research the topic of the "doxastic experience".
The nature of how our beliefs about reality impact our inquiry is an interesting slice of the proverbial pie that is the doxastic experience. Removing the term “god” and/or “God” and replacing it with "reality" or "reality's rock-bottom" and so on clears out some of the clutter and helps us focus on that interface of belief/inquiry.
Several initial, upstream beliefs held by Non-Theists compel them into some rather unfortunate downstream consequences. The intellectual price tag some are willing to pay becomes evident as they trade away logical lucidity for this or that (...ultimately...) self-negating – or illusory – possibility.
The proverbial reductio ad absurdum finds it way in through the likes of Brute Fact and through the likes of the ultimately illusory bedrock of the “….useful but not true….” syntax of navigations akin to Poetic Naturalism, and through various other examples of those downstream consequences. The ultimately self-explanatory is (...obviously...) juxtaposed to those sorts of choices. As to how to proceed, the physical sciences may or may not be the only rational mode of inquiry with respect to reality's "rock-bottom".
Most Non-Theists and Theists who are well published come to the end of the physical sciences and reach beyond those X's. The proverbial "Y" in the road pretty much always carries us into [A] Brute Facts or else [B] the Self-Explanatory.
The "self-explanatory" is interesting. The "Absolute's" reference frame cannot be defined in terms of the finite and so cannot land in anything other than Self-Reference. A few insightful theologians have followed that logically compelled premise and on several intriguing levels it begins to force X's which have overlap with specifically Trinitarian premises.
Regardless of where our line of inquiry takes us we find the Non-Theist's and the Theist's initial, upstream beliefs about the nature of reality fully in-play, driving their respective downstream claim-making as to just what counts as rational inquiry, as to just what counts as rational metrics. With respect to that word “regardless”, Non-Theists too often attempt to claim immunity for their own belief-state and we see this best exemplified or demonstrated in the affairs of their “one-less-god-than-you” claim of, “….my claim of Not-Your-X is “nothing-but” non-belief….”
Non-Theists want to claim immunity and therefore want to claim that some sort of magical (…inexplicable…) or non-porous barrier between those interfaces exists – vis-à-vis their own belief-state. It's fine if they want to claim, and believe, that such a thing exists. That claim itself (…of immunity…) is another interesting occurrence (...in this series of observations...). That is to say that that claim itself (…of immunity…) is another interesting belief – itself the downstream product of a long series of upstream beliefs about reality.
Reality’s continuum ruins claims of immunity. There are consequences for trading away lucidity in favor of claiming – gaining – the Brute Fact option. That move sets all lower levels as the inexplicable and that is *not* an agnostic claim *nor* a claim that we are simply limited by our tools. Then, from there, the consequences on all claim-making moves which take place in all distal locations which stream from that metaphysical fountainhead -- all downstream consequences -- suffer an intellectual price tag. Non-Theists in general fail to account for that continuum. Now, that continuum and those downstream consequences are fine if Non-Theists want to believe in those and in their claim-making, however, it is the upstream beliefs about reality which lead Non-Theists into those unfortunate tar pits which are of interest here with respect to the fallacious nature of the Non-Theist’s claim of “….my claim of Not-Your-X is “nothing-but” non-belief….”
With respect to that continuum, the Non-Theist’s claim-making-move to assert and/or argue that such a magical (…inexplicable…) or non-porous barrier between upstream beliefs and downstream claim-making-moves actually exists (….presumably within that continuum….) is in part motivated by the Non-Theist’s desire – want – to claim that his claim-making is constituted of “nothing-but” the stuff of “no-beliefs” with respect to reality. Observational reality therein seems to affirm that Non-Theists want to claim immunity and therefore want to claim that some sort of magical (….inexplicable….) or non-porous barrier between those interfaces exists. Again, it's fine if they want to claim, and believe, that such a thing exists. That claim itself (…of immunity…) is another interesting occurrence (...in this series of observations...). That is to say that that claim itself (…of immunity…) is another interesting belief – itself the downstream product of a long series of upstream beliefs about reality.
The World is Flat:
The growing tide of younger, bolder Non-Theists are eager to deconstruct, eager to get to the point, and they’re not afraid to let go of yesteryear’s brand of Atheism’s muddied and hedge-filled attempts to retain necessary transcendentals. “Ultimately absurd? Sure. So what? It’s enough to get by on…..” as the likes of, say, Sean Carroll’s Poetic Naturalism and other such T.O.E.'s run to the edge of reality – truly believing that reality is in fact flat – such that they truly believe they have found reality’s edge – and truly believing there are no catastrophic consequences to taking the proverbial ship over the Flat-World’s edge where lucidity in fact ends as they race towards reality’s epicenter with respect to that pesky trio of “Being Itself” and Brute Fact and the Self-Explanatory. “But it’s enough to get by on!” and various forms of "Sure, it's useful but not true! So what?" end all such polemics against reason’s demands for lucidity through and through. For a bit more context see http://edwardfeser.blogspot.com/2013/10/why-is-there-anything-at-all-its-simple.html as to "Why Is There Anything At All? It's Simple".
Regarding the Flat World, the Non-Theist must not react too quick in his attempt to deny that he in fact does affirm such a world. The edge of the world just is the end of lucidity and such finds the illusory within the useful-but-not-true. That growing tide has displaced the timid Non-Theists of yesteryear who still hold on to their bizarre attempts at ontological cul-de-sacs, while the younger, bolder brand is far more eager to get to the point. Now, of course we don't know the end of all physical systems and if the Non-Theist claims his agnosticism with respect to such systems, well then all that we can is that his move to agree with Christianity regarding physical systems is fine.
The Non-Theist’s World is not a Flat World “only because” we do not understand all of reality with respect to the physical sciences *nor* is it "only because" we do not understand all of reality with respect to all that lies beyond the metrics of the physical sciences. For in fact the Christian actually claims that there is that which awaits ahead – up over the horizon – which Scripture tells us is beyond all that we can ask or think. Hence the Non-Theist’s attempt to address the question on the table by employing his appeal to his belief-state being agnostic with respect to the ends of the physical sciences and/or all which awaits us beyond physical metrics is evidence that he does not understand the nature of the problem he thinks he is – but is not – addressing.
The “Flat World” is not Flat on Non-Theism because we do not understand all of reality, but, rather, it is the Non-Theist’s conflation of [A] that gap in knowledge for [B] an inexplicable intellectual right to [irrationally] embrace the absurd and reject logic and lucidity.
Non-Theists do the Christian's work for us here as they follow logic and reason into the various cousins of solipsism. From there logic forces our hand into either a reductio ad absurdum or else into a reductio ad deum. Diving into "Being Itself", which is the question on the table, is too often avoided by too many Non-Theists as, based on standard replies, such discussions don't follow upstream premises far enough downstream to address the actual question on the table with respect to the trio of  "Being Itself" and  Brute Fact and  the Self-Explanatory.
The Edge of the Non-Theist's Flat World just is the end of lucidity and such finds the illusory within the useful-but-not-true steering the ship. Not through this or that "layer", but in fact through and through. It's all about layers. Too often our Non-Theist friends talk as if a gap in knowledge is the point. It isn’t. The point is quite simple and it is the Non-Theist’s Edge there at the end of lucidity such that his complaint turns on the subtle but unavoidable premise that he has a reality in mind that is beyond mind, beyond lucidity, and beyond logic. In their appeal to their belief-state and this or that layer of agnosticism in their attempts to deny that they do in fact affirm that the world is flat, they are already making one category error with respect to the term Reality and the term Edge. Often they do not recognize that and actually think – half way through these sorts of discussions – that the goal posts have changed, but that merely implies that they’ve not begun to understand the Christian’s metaphysic. Much less address its premises. Non-Theism’s logical progressions into the trio of  "Being Itself” and  Brute Fact and  the Self-Explanatory just is the T.O.E. (….Theory Of Everything…) which affirms that The World Is Flat.
Before going further, a brief comment on love:
We see that same "Non-" pressing in upon love and empathy (…it must be for the World is, the "Non-" tells us, truly Flat…) as irreducible indifference is traded on in the Non-Theist's polemical sonnets  against Theism and  in defense of love and empathy. The rational with respect to reason as truth-finder cannot be ontologically seamless with the moral given the No-God paradigm wherein irreducible self-giving trades on irreducible indifference and the convertibility of the transcendentals is finally illusory. Given the No-God paradigm what reason claims to apprehend is (….given the non-convertibility of the transcendentals…) ultimately unable to traverse the ontic-ocean from the good and the beautiful and to the real. She (reason) in her proper role as truth-finder is obligated to chase after what *is*, after *facts* and justifiably so. As such the Non-Theists Hume, (physicist) Sean Carroll, Alex Rosenberg, Michael Ruse, and countless others find no obligation on reason's part to prefer, chase after, the scratching of one's finger over the destruction of the world. That is to say that the "morally *un*-reasonable" is, simply, impossible given the No-God paradigm wherein irreducible self-giving trades on irreducible indifference and the convertibility of the transcendentals is finally illusory.
Whereas the Trinitarian processions of love's timeless self-outpouring find that the rational with respect to reason as truth-finder is in fact ontologically seamless with the moral. Therein (to borrow a phrase from E. Feser) “….what reason therein apprehends is (given the convertibility of the transcendentals) as good and beautiful as it is real….”. The thoroughly Trinitarian metaphysic presents us with the timeless diffusiveness of self-giving as such relates to the Ontic-Self in totum which of course presents reason with reality's irreducible substratum. There again we find that in any No-God paradigm what reason claims to apprehend is (given the non-convertibility of the transcendentals) ultimately unable to traverse the ontic-ocean from the good and the beautiful and to the real.
On a few levels that is in part akin to the concept of the eternally open-ended continuum which metaphysical naturalism forces even as that same paradigm inexplicably attempts to lay claim to “goals” within this or that ontological cul-de-sac or stratum or echelon. But “eternally open-ended goals” just won’t do and for all the same reasons that “ontic-cul-de-sac” just won’t do.
Moving on and pressing in on definitions:
"Non- ’s" of all strips do our work for us as in navigating to the Edge of what they claim is the Flat World of Lucidity. They (…."Non- ’s" of all strips….) typically follow reason and logic and end up within various cousins of solipsism, both hard and soft, which of course is again what the Christian’s metaphysic predicts as that proverbial “Y” in the road between the Divine Mind (on the one hand) and Absurdity (on the other hand) approach ever more rapidly.
Reducibility, contingency, mutability, and brute fact just won’t do. The metaphysical absurdity which the "Non-" is forever the victim of is his own attempt to make the difference between Being and Non-Being something akin to just a little less than infinite. There again the pains of those supposed “ontic-cul-de-sacs” are supposed to be an anchor whereby the Non-Theist really can – while using his GPS – “simultaneously” [A] travel over the Edge of what he believes to be a Flat World and [B] go on talking “as-if” the World is Round. Whether it be logic and love, whether it be reason and reciprocity, or however one wishes to phrase it, such does not change the conclusion.
The Atheist’s athe-ism:
The ism is not about what he rejects. It's not "A-"
The ism is not about his self-report on evidence. It's not "A-"
It is, rather, about what one delights in, what one affirms, what one gives intellectual assent to, what one embraces.
It is about what one loves.
And what is that? The reductio ad deum and the reducito ad absurdum press in and find that such will be – in the full light of day – the Edge of a Flat World and what one trades upon in order to affirm the reliability of his GPS – namely [A] the absurd or the non-rational and [B] the illusory or the non-real, and – finally – [C] the indifferent and loveless or non-love. It is an irreducible substratum. It is the "Non-"
Such is Non-Theism.
In closing, an observation:
On occasion the Non-Theist will avoid the question all together and claim that there is a fundamental difference between the concept of “GOD” vis-à-vis the Bible/Scripture (…on the one hand…) and the concepts relating to the source of reality (…on the other hand…). Such a move displays an unawareness of the Christian metaphysic as it relates to what it finds in logically forced steps carrying reason into a thoroughly Trinitarian metaphysic. A brief discussion under the "Define God" tab looks at the following:
A Thoroughly Trinitarian Metaphysic:.
An excerpt for direction and context:
The topic of mapping reality carries us forward in our inquiry. The map of “Being Itself”, which of course is not the territory, begins to take shape:
[A] is not [B]
[B] is not [C]
[C] is not [A]
Each is Being in totum, each is *GOD*. Both  Logic and  Love’s timeless reciprocity compel reason (…in her proper role as truth-finder….) into a thoroughly Trinitarian metaphysic.