What do we know so far about the necessary entity we are calling Entity X? We know that it must:
1) Exist and always exist
2) Be without a beginning
3) Not be dependent on anything else
4) We should be able to reason to its existence simply by describing its essence
5) We cannot form a coherent picture of reality without including this thing.
Given these 5 initial assumptions that we have talked about, we can rule out a number of things as the necessary Entity X.
First, anything that exists in our universe cannot be necessary since everything in our universe is contingent. Scientists think that it is logically possible that there exist multiple universes all with different laws, different creatures, or no creatures etc. This makes any one of them and everything in any of them, by definition contingent of course. We need go no further than this, but just for fun let’s look at some other reasons nothing in our universe meets the criteria for Entity X as we have defined it.
There is also evidence that our universe began at the big bang. If of course it began it time or simultaneously with time, then by definition it cannot be Entity X as per our previous discussion
Second, anything that is caused or explained by some deeper truth or reality cannot be necessary. Since it is likely that any universe “began” and all potential universes themselves are dependent on a deeper set of laws, some people might find the laws of physics as a very appealing ultimate explanation of things. It seems scientific and entirely plausible. If someone asks “Why do I exist? Then we could respond with “Well because of your parents”. Why do you parents exist? Well, we answer… because of their parents and so forth. We could trace that back through evolution all the way to the primordial goo from which Richard Dawkins believes life arose, or any other ultimate cause. We could trace this primordial “goo” or chemical soup back to the beginning of the earth and even the galaxy itself. (Recall the late Carl Sagan’s line that we are all “star stuff”.) We could trace all this back to the beginning of the universe itself. At that point we might say that the laws of physics are the ultimate cause of the emergence of a “universe” from, well something called the quantum vacuum (the vacuum would itself be contingent and need an explanation of course but I digress….) Similarly, even if we do not want to form a chain moving back in time, we might want to describe reality the way it is observed in the here and now. Why is the coffee cup three feet above the ground? We answer “Because it is on the desk”. Why is the desk held up? “Because it is supported by the floor”. Then from here we can reason the floor is held up because of the earth, the earth held in place by the sun, the sun by the center of the galaxy, the center of the galaxy is itself rotating around another center (some sort of black hole) and on until some central figure. We might then ask what keeps this central thing intact and we might say the laws of physics are keeping it both in place and functioning so as to exert sufficient gravitational and other forces to ultimately explain the coffee cup resting on the table. In both of the last two examples, the laws of physics serve as an explanatory ultimate.
We shall see why this answer is inadequate.