These are the positions the word “atheist”
covers, and the neighboring words it is confused with. Each
is stated as its own advocates state it.
Atheism
Strictly, the position that there is no God — or, in
a weaker and now common usage, simply the absence of belief
in one. The two differ in what they must defend: the first
makes a claim about reality and carries a burden of proof;
the second claims only a psychological state and carries
none, but also settles nothing. Much confused debate comes
from a speaker sliding between them — asserting there
is no God, then retreating, when pressed, to “I
merely lack belief.” Worth deciding which you mean.
The positive arguments are weighed in
Arguments Pro and Con.
Agnosticism
The position that the existence of God is unknown, or
unknowable. It is not a halfway house between theism and
atheism but a claim about knowledge rather than
about God — and it comes in a modest form (I do not
know) and a strong one (no one can). The strong form is
itself a substantial claim needing defense, since to say
the question is unanswerable is to claim to know something
about it.
Naturalism
The view that nature is all there is — no gods, no
souls, no purposes built into things, nothing beyond the
space-time-matter system and its laws. This is the real
engine of most modern unbelief, and it is a
worldview, not merely a denial: it makes positive
claims about what exists and answers for them. Naturalism
is where the interesting arguments live — over
mind,
morality, and
the intelligibility of the world — and it should not
be granted for free as “just not believing in extra
things.”
Physicalism (or Materialism)
The sharper thesis that everything that exists is physical
— describable, in principle, by physics. Stronger
than naturalism, since a naturalist might allow
non-physical natural facts; a physicalist will not. The
hardest test case is consciousness: whether the felt
quality of experience can be physical at all is the
subject of Can Matter Think?
Scientism
The claim that science is the only, or the only reliable,
source of knowledge. It is not itself a scientific claim
— no experiment establishes it — which is the
standard objection: scientism fails its own test. Most
scientists are not committed to it; it is a philosophy
about science, and a self-undermining one, treated in
Are Science and Faith Enemies?
Moral Anti-Realism
The view that there are no objective moral facts —
that “cruelty is wrong” states no truth about
the world but expresses a feeling, a convention, or a
command. Crucially, this does not follow from
atheism: many atheists are moral realists,
holding that objective moral facts exist without God. The
moral argument for God is therefore not “atheists
can’t be good” — they plainly can —
but a contest among accounts of what grounds
moral obligation, taken up in
Can We Be Good Without God?
Secular Humanism
A positive ethical stance — human dignity, reason,
and flourishing pursued without religion — rather
than a claim about God’s existence. A secular
humanist is usually an atheist or agnostic, but the label
names what he affirms, not what he denies, and much of
what it affirms the Christian affirms too. The interesting
question is whether its values are better grounded in the
worldview it rejects than in the one it keeps.
The God Being Denied Matters
One more distinction decides more debates than all the
others. The “God” most atheism rejects is a
being among beings — a very large, very
powerful person inside the universe, of the kind
What Do We Mean by “God”?
distinguishes from classical theism’s God, who is
not an item in the universe but the reason there is a
universe at all. A great deal of atheist argument is
unanswerable against the first God and simply misses the
second. Before asking whether God exists, it is worth
five minutes on which God is meant — because the
village atheist and the classical theist frequently agree
that the village atheist’s god does not exist.
Where to Go Next
If you have located yourself above, the
skeptic’s path
walks the section in dependency order — definitions,
then arguments, then objections, then history — with
the skeptical case stated first on every page. The one
request this page makes is the one Proverbs makes: let the
other side finish before you decide it has lost.
