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Does the universe need an explanation outside itself if it already has its physical laws that even allow us to think of "self-creation"?
Author: Javier Sánchez Cañizares
Published in: 50 Questions on Faith, 14
When we speak of "explanation", we must be very precise about what we want to explain, because, for the same event, there can be different levels of description. Thus, for example, the explanation for Messi falling to the ground in a football match is varied: it is due to the force of gravity, to his having tripped over an obstacle on the pitch, to the tripping of another player or to his own intention to trick the referee into calling a foul (I leave it up to the reader to decide between the last two possibilities, which are mutually incompatible).
The universe has natural explanations, which are investigated by science. It is about understanding how, from very basic physical processes, the universe is as we know it (with galaxies, stars, planets and life). Today, the most commonly accepted model for this subject explanation is the Big Bang theory, which says that the universe started from a space-time singularity about 13.7 billion years ago. By a singularity, we mean that we do not know what happened at that time, because the laws of physics no longer work there (the relevant quantities become infinite).
The Big Bang model is the one that best fits the available experimental data. However, there are other theoretical models (such as Hartle and Hawking's boundary condition-free universe, Penrose's conformal cyclic cosmology or multiverse theories) that attempt to encompass the Big Bang in a broader theory that avoids the initial singularity. It must be said that these models have, at present, no experimental support. That is why the Big Bang is still the model most widely followed by scientists.
But what would happen if new measurements proved one of these models right? We would simply be facing the usual way in which science advances, where experimental tests end up deciding which theories best explain the observed reality. That is why the Big Bang model , like all scientific model , is a model provisional that can be improved eventually.
These are all physical or natural explanations of the universe. They explain it on the basis of a series of natural transformations (from one evolving reality to another). However, such explanations fail to answer a more radical question we can ask: Why does something exist rather than nothing exist? If we try to answer this question by resorting to natural laws, we would not find an answer, because we could still ask: Why do these laws exist?
We say that the universe needs an explanation "outside" itself, not in terms of physical laws, but to answer this radical question. The ultimate reason for the existence of the universe is studied by philosophy and theology. Following the rational path proper to these fields of knowledge, distinct from and complementary to that of science, we come to know that the universe has a necessary cause (which exists by itself and cannot not exist) outside of itself; and that this Cause is God, who created the universe, with its natural laws, out of love.
Thus, when we speak of creation, we refer to the ultimate reason for existence. That is why the concept of "self-creation" is in itself contradictory. That which is not cannot be responsible for its own being. That which needs to be created, because it might not be, does not have in itself the reason for its being and cannot "create itself". So, we affirm that the universe must have the ultimate reason for its existence in another being, whose existence is necessary, whom we call God.