I'm on a John Anderson jag at the moment and I'm having a blast. (Whatever else you say about philosophy it is a marvellous and marvellously reliable source of deep pleasure, at least to those to whom she has revealed herself and who have become her life-long acolytes.) Anderson (1893-1962) is a fascinating character both as a man and as a philosopher. More importantly, if he is right, I am wrong. For I am committed to modes of being both by these pages and by my published writings, chiefly, my 2002 book on existence. Central to Anderson's position, however, is that there are no levels of reality or modes of being. So intellectual honesty requires that I see if I can meet the Andersonian challenge. My first Anderson entry is here. Read that for some background.
Here is an Anderson-type argument against a Berkeley-type position.
Suppose it is maintained that there are two different modes of being or existence. There is, first, the being of perceptual objects such as the tree in the quad. For such things, esse est percipi, to be = to be perceived. And of course perceivedness is not monadic but relational: to be perceived is to be perceived by someone or by something that does the perceiving. These perceivers or knowers exist too, but in a different mode. For their being cannot be identified with their being perceived. Clearly, not everything can be such that its being is its being perceived. Such a supposition is scotched by the vicious infinite regress it would ignite. For if the being of God were his being perceived, then there would have to be something apart from God that pereceived him. And so on infinitely and viciously. So if the being of some items is perceivedness, then there must be at least two modes of being.
But of course knower and known stand in relation to each other. So the Andersonian begins his critique by asking about the concrete situation in which I know a tree, or God knows a tree. (Cf. A. J. Baker, Australian Realism, Cambridge UP, 1986, p. 26) What mode of being does this situation have? Does this situation or state of affairs exist by being perceived or by perceiving? Neither. The fact that I see a tree exists. But the existence of this fact is not its being perceived. The existence of the fact it not its perceiving either. The fact exists in neither way. It has neither mode of being. Therefore, the Andersonian concludes, the dualism of two modes of being breaks down. There is only one mode of being, that of situations. As A. J. Baker puts it, "that situation and its ingredients all have 'being' of the same single kind." (26)
The above argument is a non sequitur. It goes like this:
1. There is the relational fact of my seeing a tree.
2. The being of this fact is not its being perceived.
3. The being of this fact is not perceiving.
4. There are not two modes of being, the being of objects of perception and the being of subjects of perception.
5. There is only one mode of being, that of facts or situations.
Both inferences are non sequiturs.
To get to the desired conclusion one needs the premises of the following argument, premises that are far from self-evident:
6. The smallest unit of existence is the situation (state of affairs, concrete fact).
7. Nothing exists except as a constituent of a situation.
8. Situations are not represented by true propositions; they are true propositions.
9. Existence = truth.
10. There are neither degrees nor modes of truth.
11. There are neither degrees nor modes of existence.
12. Knowers and things known exist in the same way.