Good question!

I don’t know, but the fact is that in certain contexts they mean different things. Although being and substance are related and sometimes coincide, the former can refer to a referent more fundamental than the latter. Substance tends to have a more specific meaning:

This conception of substance derives from the intuitive notion of individual thing or object, which contrast mainly with properties and events. — SEP

So in a process metaphysics, you have dynamic beings, as opposed to things—or maybe things are seen as dynamic beings. In any case, I don’t know about the ontological difference, but the words/concepts certainly can be different.

There is another example that came up in my reading the other day. In the paralogisms of pure reason in the CPR, Kant argues that the “I think” cannot be said to be a substance, though there is a logical or transcendental subject. I wondered if this was an example of being (transcendental subject) vs. thing (substantial immortal soul).

Right. I should highlight the fact that I re-opened the thread because I found what I consider an important book, Thinking Being, Eric Perl, from which I drew the following quotation, because I thought it relevant to the prior debate, and in favour of the ontological distinction I was seeking to draw in the first place:

All things, even inanimate ones, must have some form, or they would not be anything at all. But living things have a distinctive and superior kind of form, called ‘soul.’ For a living thing is far more integrated, more one whole, than a non-living thing. The unity, and hence the identity and the being, of a non-living thing is little more than the contiguity of its parts. If a rock, for example, is divided, we simply have two smaller rocks. In a living thing, on the other hand, the members of its body constitute an organic whole, such that each part both conditions and is conditioned by the other parts and the whole. A living thing is thus one being to a far greater extent than a non-living thing. It evinces a higher degree of unity, of integration, of formal identity, and its soul is this very integration of its parts into one whole. As such the soul is the reality of the living thing, that in virtue of which it is what it is and so is a being: “For the reality is the cause of being to all things, and to live, for living things, is to be, and the soul is the cause and principle of these” (De An. Β.4, 415b13–14). Life in living things, then, is not a character superadded to their mere being. Rather, life is their being, the higher, more intense mode of being proper to living things as distinct from others.

The distinction between living and non-living things is therefore not a mere ‘horizontal’ distinction, as if all things are equally beings, of which some are living and others are not. It is rather a ‘vertical’ or hierarchical distinction: a living thing is more a being than a non-living thing, in that it is more integrated, more a whole, more one thing. (p110) — Eric D Perl Thinking Being - Introduction to Metaphysics in the Classical Tradition

It is this distinction which I say has been occluded by the fact that physicalist ontology only allows for one kind of fundamental substance, namely, the physical, so it can't allow for an in-principle difference between beings and things, of the kind that Aristotlelian philosophy refers to here. (I was told that I was 'bordering on insanity' by one of the mods for bringing it up, speaking of insults.)

I'm quite happy to leave it at that, though.

It is this distinction which I say has been occluded by the fact that physicalist ontology only allows for one kind of fundamental substance, namely, the physical, so it can't allow for an in-principle difference between beings and things, of the kind that Aristotlelian philosophy refers to here. (I was told that I was 'bordering on insanity' by one of the mods for bringing it up, speaking of insults.) — Wayfarer

Okay, so according to Aristotle, for living beings, living constitutes their being. I can go along with that. I don’t know my Aristotle well enough to know if Perl’s interpretation is correct, to the effect that living beings are more beingy than non-living beings, but I can go along with that too if pushed. (It does not, of course, follow that rocks are not beings.)

You’re right that a distinction has been lost in the physicalist paradigm. This is because physicalism has no need for the general concept of being. But it’s crucial, I reckon, not to respond to physicalists by using being in a way that is equally as restrictive as their concept of existence. It’s good to have a general notion that is uncommitted, and that’s what being is. To stick to the grammatically basic meaning is to preserve the non-physicalist notion, even though it doesn’t assert—indeed, partly because it doesn’t assert—anything about consciousness.

(I was told that I was 'bordering on insanity' by one of the mods for bringing it up, speaking of insults.) — Wayfarer

I think @Mikie took you to be repeating your claim that the word “being” refers only to conscious referents. Perhaps he wasn’t right about that—and calling you borderline insane was mildly bad—but it was understandable, because in fact you have conflated the issues.

he unity, and hence the identity and the being, of a non-living thing is little more than the contiguity of its parts. If a rock, for example, is divided, we simply have two smaller rocks. In a living thing, on the other hand, the members of its body constitute an organic whole, such that each part both conditions and is conditioned by the other parts and the whole. A living thing is thus one being to a far greater extent than a non-living thing. — Eric D Perl Thinking Being - Introduction to Metaphysics in the Classical Tradition

I don't think Perl portrays this very well, and he seems to oversimplify a very complex issue. The temporal continuity of material substance, which is what we tend to associate with the existence of an object with mass, is not well understood by human beings in general. The unity of a rock is far more complicated than simply an existence of smaller parts, with all the characteristics of the larger rock, consisting in a contiguous manner. That description could be called an ignorance.

Scientists have found multiple levels of unifying principles which dictate the possibilities of dividing a whole body with mass. These levels include molecular binding, chemical bonding, and the strong force of the atomic nucleus. Since the strong force is responsible for the existence of mass, in general, and it is not at all understood, statements like Perl's are not well founded.

Having said that, I do agree that the unity which constitutes a living being is quite different from the unity which constitutes an inanimate object, and this difference is mainly attributed by scientists to the organization of the parts. The chemical bonding of organic matter is extremely complex and unstable, and this allows for the capacity for all sorts of activities performed by the living being. However, since we do not understand the strong force which unites the mass of an atom's nucleus, and how this force relates to the forces of chemical bonding, we really have no understanding of the difference between the unity of a living thing and the unity of an inanimate thing.

It appears to me, that it is very possible, and likely, that the unity of the atomic nucleus which constitutes the existence of temporal mass, extends deeper than the unity which is associated with living beings. This would mean that mass in general is prior in time to life, and that would account for the reason why the activities of living beings is limited by mass, and free will is not unbounded. Accordingly, contrary to Perl's portrayal, the inanimate unity which constitutes the fundamental existence of mass, produces a deeper and more substantial "whole" than the "organic whole". And of course we observe this throughout the universe, whole's like the solar system, the galaxy, etc., which are far more substantial than the organic wholes found on earth.

Being is a very complex word when it comes to philosophy . If you are going to say consciousness is the precondition of being then you have to clearly define what you meant by being. Is it ontic or ontological. If you refer existentialism there are beings without consciousness in some of their philosophy. Heidegger's dasien is different from all of these and is much more complex.

but I really don't think it makes sense to declare that anything that exists is 'a being'. — Wayfarer

Good lord.

Being is a very complex word when it comes to philosophy — Abhiram

No kidding. I’ve only been discussing it at length for 5 years. So with all due respect, spare me.

You’re right that a distinction has been lost in the physicalist paradigm. This is because physicalism has no need for the general concept of being. — Jamal

Thank you. That’s been the point at issue all along. I’ll only add that the term translated as ‘soul’ in that passage, as something which characterises living beings, is the Greek ‘psyche’, which, of course, can also be translated as ‘mind’, depending on the context.