eternitygram

Eternitygram is a concept introduced by the philosopher David Lewis in his 1973 paper "Eternity and Time." It is a theoretical model that aims to reconcile the apparent tension between the eternal nature of the universe and the temporal experiences of individual beings. The idea is that the universe is eternal, meaning it has no beginning or end, but time is experienced as linear and finite by each individual.

In the eternitygram model, the universe is represented as a two-dimensional grid, with one dimension representing the temporal flow of time and the other representing the spatial dimensions. Each point on this grid corresponds to a possible state of the universe at a particular time. The temporal dimension is not linear but rather circular, with the present moment being a point on this circle that moves continuously.

Individual beings, or "worldlines," are represented as lines that traverse this grid. Each worldline corresponds to the temporal experience of an individual, with the present moment for that individual being the point where their worldline intersects the present moment on the temporal circle. This model allows for the possibility of multiple timelines and the existence of beings that are not bound by the linear flow of time.

The eternitygram model has been influential in the philosophy of time and has been used to explore various temporal paradoxes and the nature of personal identity. However, it is important to note that the eternitygram is a theoretical construct and its empirical validity remains a subject of debate among philosophers and physicists.