My argument against materialism (=matter is all that primarily exists, everything else are configurations thereof) is really simple:
1. All empirical observations are dependent upon consciousness.
Yes. This is just the Kantian divide into the
phenomenal and
noumenal realms.
(A
lot of people confuse the
phenomenal and
noumenal realms with the
subjective and
objective realms, which is of course very wrong as our entire experience of the
objective world - including such things depth, distance and colour, etc, are in fact being produced by our minds/brains.)
What lies underneath our
psychophysiological construction of reality, i.e the true
fundamental essence of reality (and the 'things'/'bodies' therein) is
unknowable.
In a more simpler sense, we just have to accept that we can't look at the universe from the outside-in. Therefore
all statements about metaphysics (i.e. the
fundamental nature of
neumenal reality) are conjecture, theory, hypthetical and/or faith and belief based.
2. Materialism claims that there is something independent of consciousness (matter).
More accurately, it is
realism that is the claim that there is an extant (existing)
neumenal reality "out there" that your mind-brain senses (through the five physical senses) and constructs into the objective world of your experience.
And
realisim is rather easily demonstrated as, at least, somewhat valid by simply leaving a working timepiece in an empty room and forgetting about it for a while. When you return the hands on the clock will have moved the same amount of time that you were out of the room.
Now, the process that describes how the hands on the clock work is called
naturalism. Whether it's a battery operated wristwatch or a wind-up grandfather clock it's just the stored
potential energy in the battery or springs that's being released as (and converted into)
kinetic energy over time that makes the hands move. And, of course, if nobody ever changes the battery or winds up the clock it will eventually stop working.
So, so far we have an outside universe that is both
real and
natural.... now for
materialism.
Materialism is the claim that things are made of something that is basically tangible, that they have substance and volume and occupy a fixed location in spacetime (i.e. that 'things' have a
corporeal substrate.)
In the modern world the term
materialism really is more applicable to discussions concerning
classical, Newtonian physics. (When discussing things like massless photons and wave-particle duality many people will use the term
physicalism instead of
materialism for obvious reasons.)
One important thing to remember here is that we are
evolutionarily and
developmentally primed towards a
materialistic view of reality.
Like our pre-human hominid and simian ancestors, babies have no interest whatsoever in massless photons and double-slit experiments. None.

Their brains are instead asking "What is this colourful thing?" and "Can I eat it?", etc.,.
3. Empiricial evidence of something independent of consciousness needs to be independent of consciousness.
4. Because of 1. there can be no such evidence.
5. Therefore: Materialism can never have empirical support.
6. A position that can never have empirical support is worthless / false.
I understand exactly what you mean here but you have to remember just how wide in philosophical scope the
phenomenal/neumenal divide is.
In short,
no metaphysical theory about neumenal reality (that is, the true fundamental essence of spacetime and 'things') can ever be anything other than theoretical.
And that includes all ideas about what type of God/s, soul-creators, brains in vats or magic self-generating and self-perpetuationg substances and powers are really "out there" underneath and/or behind
reality.
So instead of materialism, idealism (=consciousness is the fundamental reality) seems to be more sensible. Because all observations (which are the basis of all science) rely on consciousness, it seems logical to assume it is fundamental to the knowable world. Of course if we weaken the definition of materialism enough, so that consciousness and matter are co-dependent, or matter is fundamentally equal to consciousness, materialism and idealism are really the same. But I don’t think most materialists would take this position (if you do, I don't object to your form of materialism).
We also could conclude that we don’t (or cannot) know what the basis of reality is.
Most probably this argument is not new, but still many people (especially here) believe in materialism. So what do you think is wrong with this argument? Or if you don't think something is wrong with it, what do you think someone could find wrong with?
Well, yes....
I have a conscious mind that can create, store and retrieve information. Therefore, applying Occam's razor (not wishing to multiply unknown entities) the best theory, quite clearly, is that the
unknowable foundation of reality (unknowable, at least, through
empirical observation) is a conscious mind rather than a
purely theoretical magic powder (of power).
Effectively, phenomenalistic theism (in either the Berkleyian or Kantian metaphysical sense) is just arch-skepticism about claims about the ultimate nature of reality.
In short, why theorise something unknown and unknowable as the true
funadmental essense of things when we already have something in consciousness that can create, store and retreive information?
~
HypnoPsi