The problem with the sea shell argument (or the old "watchmaker" argument) is that it assumes that all ordered things demand a creator. It is an attempt to answer what is, in effect, an unknown. It might be plausible, when men first thought about atoms and the like, to assume that their orderliness came from a creator or an "orderer" of some kind. And this is a BIG assumption mainly because we, as people, order things. However, we discover that some things just naturally order themselves. For example, if I drop a zillion BB's in a jar, you end up with the BBs being very ordered (and the outcome is incredibly predictable). This is not due to me arranging them, but to things like their shape, the shape of the jar and gravity. The same is true for molecules (as an example). There are many, many examples in the universe of order that happens without a designer behind the scenes.

What really is going on is that God (or the concept of God) gets the blame/credit for whatever we don't know about. When we did not know how diseases came about, we blamed God. Now we know better and we no longer blame God. When thunder and lightening caused us, as a people, to cower in fear, we accused some deity. Now we know the process of these events and most of us do not get frightened any longer by them. However, there are still things that we do not understand. As a result, many people still blame/credit God with them.

One such example is what happens after we die. This is something that mankind does not know about as we have not devised a way to test it with certainty. Once again, a deity gets the blame/credit. The same is true with the origins of all things. Where did all this come from? We don't have an answer (yet). Therefore, it is an unknown. And, as a result, many will give the credit to some deity.

In ancient times, the deities were accredited with virtually everything. These days, very little is accredited to him/them. As time goes on and more unknowns become known, less and less credit will be given to any deity.