One standard alternative to standard materialism is dualism: minds don’t just arise from matter alone but require a further, distinctly mental ingredient. Another standard alternative is what I’ll call classical idealism: minds didn’t arise from matter, but the other way round, matter arose, somehow, from minds.
Hofweber rejects both of these relationships (dualism & classical idealism) between mind and matter: “but for the debate about idealism they are wrongheaded”. He goes on to say:
The real issue about idealism is not simply about matter and how it relates to minds, but about the place of minds in reality. Idealism is better seen as a label for the vision that minds are central in reality.
H is claiming that minds are central to reality but in a different way than we have previosuly conceived. In particular, language entails strong idealism:
How could one hope to establish a metaphysical conclusion like idealism from considerations simply about our own language? … Let us call strong idealism the thesis that our human minds are metaphysically central to reality.
This is the type of idealism we support on this website. The idea that the way we perceive, and can only ever hope to perceive, reality is through language.
The concept of reality can in general be understood, or precisified, in two ways: the totality of what there is, or the totality of what is the case.
The ‘totality of what there is’ means the totality of the physical world: electrons, atoms, molecules etc (ontological idealism). The ‘totality of what is the case’ means the totality of the linguistic. What can be expressed in language (alethic idealism).
H’s argument from here becomes a little complicated but it boils down to the fact that reality for us is what can be expressed (or effed) in language. If it is effable, it is part of the totality of what is the case. If it cannot be effed then it can be lumped with the ontology (but we will never know if we are correct in doing this).
Thus a dinosaur for example that lived in the past before the human (linguistic) mind came on the scene did exist from an ontological point of view but not as a “dinosaur”. It existed as a part of the physical world. How we conceptualise of that group of reptiles and the world that existed pre-mind is for our minds to determine.
This in particular means that reality, understood as all there is, does not include reality understood as all that is the case. The facts are not just part of the things. And this opens up a special kind of possibility: the possibility that what there is is independent of us, but what is the case is not.
In the above, H is suggesting that facts (or propositions) are not part of the physical world. They are products of our mind and in particular language. And so we come to the header quote that brought you here:
The ontology of the world is one thing, it is simply there. But the propositional aspect of reality is something quite different.Thomas Hofweber (2017)
Science is concerned with the ontology of things – what there is, how can we manipulate it. But reality is really a product of our mind. H suggest ‘propositions’. I have argued elsewhere however that we do not need to propose propositions. We have language and that is all we can know.
Hofweber, T. (2018) “Conceptual Idealism Without Ontological Idealism: Why Idealism Is True After All” in Idealism: new essays in metaphysics, T. Goldschmidt and K. Pearce (Eds). Oxford University Press