so forth for other truths about the past. PEP does not face the truth-making objection
that devastates presentism, despite the fact that PEP implies that there is a meta-
physically fundamental sense in which no past objects exist.
Given PEP, reformulating the truth-maker principle as PEP-TEM is motivated.
Likewise, perhaps it is not unmotivated for the presentist to reformulate the truth-
maker principle as the view that truths are made true by things thatdo,did,orwill
exist.^39 Definethe following“quantifier”as follows: (^9) dxΦ= df. 9 xΦorW( 9 xΦ)or
F( 9 xΦ). We now reformulate the truth-maker principle as:
(Pres-TM): For allP,ifPis true, then (^9) dx(xmakesPtrue).
Grant that“ (^9) d”functions enough like a quantifier to deserve to be called one. So the
friend of Pres-TM can at least mouth the slogan that“truth is determined by being.”
But that isn’t enough.Definedquantifiers are cheap.^40 Suppose one believes that
statements about nomic possibilities are true, but is worried that their truth requires
uncomfortable additions to one’s ontology on pain of violating the truth-maker
principle. No need to worry! Simplydefinea new notion ofbeingas follows: let“L”
be theit is nomically possible thatoperator, and define“ (^9) LxΦ”as“ 9 xΦorL( 9 xΦ).”
And then reformulate the truth-maker principle as:
(TM): For allP,ifPis true, then (^9) Lx(xmakesPtrue).
But TM violates the spirit of the truth-maker principle.^41 The lesson here is that the
truth-maker principle must be formulated so as to appeal only to what exists in some
fundamental sense of“exists,”instead of appealing to defined or non-fundamental
notions of existence. And the motivation for this restriction is straightforward. Truths
about“what there is”in some non-fundamental sense must be grounded in truths
about what there is in some fundamental sense. But the problem for the standard
presentist is that, by her lights, there is exactly one fundamental sense of“exists”which
is such that nothing that exists in that sense could serve as such ground.^42
However, since PEP-TM appeals only to fundamental senses of“exists,”PEP-TM
satisfies this demand. Truth is determined by what exists in some fundamental way
or other. Past existence is a genuine kind of existence, and so truths about the past are
appropriately grounded.
3.6 PEP and Williamson’s Present-Centrism
Another view in the philosophy of time worth considering is defended by Timothy
Williamson (2002), which we will callpresent centrism. According to present
(^39) See Gallois (2004: 649). (^40) See Turner (2010) for related discussion.
(^41) Sider (2004: 679) offers a similar response.
(^42) Unless the presentist appeals to“cheating properties,”but doing so would eliminate the motivation
for endorsing Pres-TM rather than TM.