These holes, henceforth hole 1 and hole 2 , are not identical with each other. Now
God could have created just one of these universes without creating the other, and
had God done this, either hole 1 or hole 2 (but not both) would have existed. And yet,
in all other respects, there would still be the same distribution of perfectly natural
properties and relations. So the property of being hole 1 does not supervene on all
other perfectly natural properties and relations, and so the property of being hole 1 is
itself a perfectly natural property, and so hole 1 is fully real, despite being a hole.
Although this argument might seem initially plausible, it’s also resistible. Although
God could have created the universe that contains hole 1 , it is not true that being hole 1
fails to supervene on all other perfectly natural properties and relations. What is true
is that it fails to supervene on all other perfectly natural non-haecceitistic properties
and relations. If there are other perfectly natural haecceitistic properties forbeing
hole 1 to supervene upon, the sufficient condition for being a perfectly natural
property is not satisfied. And I think that there are. Perhaps the property of being
that donut is one of them, but I am more inclined to think that the various haecceities
of the fundamental particles that compose the donut are better candidates for being
perfectly natural properties. So the thought is this: the haecceity of the hole is
constrained by the haecceity of the donut, which is in turn constrained by other
haecceitistic properties, which might include those of the particles that compose it.
Good. But now we face a worry. Once we grant that at least some haecceitistic
properties supervene on others (and hence we lose the argument for their across-the-
board fundamentality), why do we think that ours do not? Perhapsbeing Kris
McDanielfails to supervene on the distribution of qualitative properties but still
supervenes on the distribution of the haecceities of my parts. To the extent that we
trust the initial motivations for thinking to the contrary, we will have a reason to set
this concern aside. But the case for our full reality admittedly feels shaky.
At this point, we’ve seen how thorny the theoretical arguments for our full reality
can be. But perhaps there is another option. Kant (1999a: 112–13, Bxxi–Bxxii)
distinguished between two ways of defending metaphysical positions: theoretical
arguments and arguments from practical reason. In the next section, we will assess
the prospects for an argument from practical reason.
6.6 Practical Arguments for Full Reality
In this section, we will explore several“practical arguments”for our full reality.
Thefirst“warm-up”argument can be stated concisely: a necessary condition of
our having the value we take ourselves to have is that we are fully real. We must take
ourselves to have the value that we take ourselves to have. So we must take ourselves
to be fully real.
Thefirst premise was defended in section 6.2, so I will focus on the second
premise. Whymustwe believe that we have a certain sort of metaphysical value?
And in what sensemustwe? One possibility is that we simply are psychologically