I see you’ve got some words about deism, but what answer have you for pandeism?
Pandeism is an interesting philosophy. It is not a religion, but a philosophcial/worldview perspective. This is certainly not now, nor has it ever been a large movement. I am not an expert on this philosophy, but my guess is that it has had a revival of popularity because of scientific evidence for the big bang. Pantheism is the philosophical perspective behind most Eastern religions. Hinduism, Taoism and Jaina are definitely pantheistic and Buddhism is, arguably pantheistic as well. The pantheist believes that the God fills up the universe and the universe is, essentially God. We are all a spark of the divine. When we die we are reabsorbed into the God/universe. The biggest problem with deism in the modern age is that it requires that the universe is eternal. If God is, essentially, the universe, then the universe cannot have been created. The Creator cannot create himself. The comology of all Easter religions is a cosmic “wheel” of time–an eternal oscillation of creation and destruction. Like I already said, this is a big problem for pantheism, because science tells us that the universe is not eternal, neither can it be eternal. The universe was created about 13.5 billion years ago out of nothing. It is not an oscillating universe. The second Law of thermodynamics tells us that the universe cannot be eternal.
Where does this leave the thinking pantheist? Classical pantheism cannot be supported in view of clear cosmological evidence. Pandeism comes to the rescue. Pandeism is a marriage of deism and pantheism. The marriage seems to be ad hoc and a weak marriage, as it appears, at first glance, to be self-contradictory. The deist believes in a Creator who created the universe but who is not personally invested in the universe. This Creator does not intervene in the universe. The Creator is not personal but rather impersonal and, obviously, distant. An impersonal universe is certainly consistent with pantheism, but pantheism has an eternal, uncreated universe. The pandeist proposes that there was an impersonal Creator who, after the creation, allowed himself to be absorbed into the universe. To the outsider, this seems like a patch-up to save pantheism in a world in which creation is clearly implied by the data. What is the nature of this Creator? How can the Creator become the creation? This is hard to explain. Remember that this esoteric philosophy is not held to by any world religion.
I am far from an expert on this philosophy, but from the little research I have done, I find no influential philosophers or teachers who have publically called them selves pandeists. Below is a quote form a pandeist web site:
And yet, both Pantheism and Deism are insufficient; Pantheism can not explain how we came to be here or why we exist in a Universe with the peculiar capacities that ours exhibits, in particular the simple form of complexity that it engenders; nor has it much insight to offer as to our purpose of existence or our moral dimensions. Deism can explain how we came to exist but can provide no reason why an entity capable of creating such a Universe as ours would be compelled to do so, nor why such an entity would appear to abandon the Universe that it had just fashioned with such care for the details of its energetic constants. And so neither Pantheism nor Deism offers a complete solution by itself. But interposed under the light of modern science, they can be brought together to offer precisely that solution.
You can see that this philosophy was created purely from human thinking in order to solve a perceived rational problem with both deism and pantheism. What is unfortunate for this philosophy is that it is self-contradictory. It is a patch-up, created to solve a logical problem, rather than based on any evidence for the truth of the philosophy.
I hope this helps.