Someone told me that there are nothing like table or chair because what there actually are is arrangement of matter and energy and label attached to it, which only exist in our minds. He thought if we accept nominalism, then we must accept this. I think he confused abstract objects with concrete objects. It seems to me that it's possible to believe things like table and chair exist while believe those concepts exist only in mind. Am I wrong?

Judging from your descriptions of them, your position seems to me more plausible than the other person's position.

If tables actually are arrangements of matter and energy to which some label (say, "table") attaches, how does that imply that tables don't exist? On the contrary, it seems to imply that tables do exist, because it implies that tables are things (namely, arrangements of matter and energy) to which that label attaches, i.e., things referred to by that label. Someone who denies the existence of tables ought not to identify tables as anything, including as particular arrangements of matter and energy.

It's true that tables wouldn't exist unless human beings (or some other species) made them: tables are artifacts. But of course it's not true that tables wouldn't exist unless human beings (or some other species) attached the label "table" to particular arrangements of matter and energy. Indeed, the very first tables probably weren't called "tables," and in most of the world tables still aren't called "tables."

Can tables exist even if the concept table exists only in our minds? I don't see why not. There's no reason to think that if a concept exists only in our minds, then whatever answers to that concept must also exist only in our minds. Similarly, just because all labels are items of language, it doesn't follow that everything that has a label is an item of language.

As far as I know, nominalists do not and need not deny the existence of tables or any other concrete entities. What nominalists are more likely to say is that if there were no minds, then nothing would have any properties: the earth wouldn't be spherical, for example. I reject that nominalist view, but even those who hold the view can agree with the rest of us that tables do exist.

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