Some philosophers of time advance non-presentist theories about time. Most of these are eternalist theories about time. Eternalism just is the position that not only present things are real. Things at other times, both earlier and later than the present, are also real.

The “moving Spotlight”

The “moving spotlight” theory holds the real present, and change in relation to it, is explained by there being a singular moment—the present—that changes in relation to everything else. Events do not change; instead, the present changes. It changes by being first at one set of events, then being at another set of events, and then yet another set of events ... and so on.

The moving spotlight gets its name from an analogy by Broad: it is as if the present changes its position in relation to events as a spotlight might change in relation to different houses on a street. First, the spotlight is on one house and then it is at another house; similarly, the present is at one event and then at another event (Broad 1923).

The order in which the present is at one event and then another event determines the events’ locations in the А-series. When the real present is at an event, the event is really present; when it was at an event, the event is really past; when it will be at an event, the event is really future. The point is that the events do not change, the present changes. The change provides real temporal passage and the real A-series.

The advantage of the moving spotlight is that it folds both temporal passage and the real present into one metaphysical entity that has a simple-seeming metaphysical feature: it is a unique present that changes (it “moves”). This explains the unity of events undergoing temporal passage. These events do not really change. Instead, what changes is the present. Events only “change” in relation to the present.

The events are like a person who never changes height; yet, because her younger brother grows up, goes from being tall to being short (relative to her brother). The events never change positions in time; yet, because the present is no longer at those events, they go from being present to being past.

Objection: Events Must Change

The moving spotlight fixes the existential or ontological status of events. The events do not change no matter how they are placed in time. However, events must change their ontological status. They must change when they become present. They must undergo what Broad calls pure becoming (Broad 1923), that is, an event becoming real. This is a fundamental change in events that is their coming into existence. As such, since no longer being future means an event becomes real, the event must be unreal when it is future.

The concept of future events as unreal is a concept of an open or unreal future. But an unreal future is not available to the moving spotlight theory: in the moving spotlight, all that changes is the present’s relation to events in the world. Events in the future do become present and past. However, all that means is that, when the present “moves” to these events, events that are future become present. These events otherwise do not change their status, ontologically or otherwise. They do not become real or come to exist; they do not undergo pure becoming.

With respect to advocating an open future in this way. presentism has an advantage over the spotlight view. According to presentism, the future is not real. As such, w'hen events become present, they come into existence. How'ever, as discussed, presentism has the problem that, for the very reasons it allows an open future, it also has problems w'ith what might be called an open past. It must explain why the unreality of the future allows an open future while the unreality of the past does not. (For extended discussion of the “moving spotlight”, see Cameron 2015.)

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