I’ve seen Atheists go after theism and even after agnosticism, but so far, I haven’t seen deism being criticized from an Atheist point of view.
In a way, I get it: they’re kind of fence-sitters who share most of our viewpoints on important issues and they could make great allies in defending secularism. There’s only this thing, they believe in the energy of the cosmos – an intelligent and conscious energy that gives life to all living things.
But the thing is, they’re are wrong and here’s why:
For all we know, in order to have either intelligence or any kind of consciousness about the world surrounding us, we need a physical body, attached to a brain enabled to decode the impulses the senses send. Without a brain, no-one could know how a flower smells, or what a steak tastes like.
In order for you to have a creative god, that may have created the Universe and just watches everything from the distance, you need a brain. Taking into account how big and unfathomable the Universe is, we should be talking about a super-sized brain, with a super-sized physical body, producing super-sized residues, and having super-sized veins and arteries pumping blood into and oxygenating said brain. And it should age!
There’s no evidence whatsoever of such a brain, or body, or remains of it. And the absence of evidence, when it should logically be there, is evidence of the absence.
Deism is an irrational idea and, as any other irrational belief, it has done harm: remember the self-defeating the “Universe conspires in your favor” meme? Well, there – how many people were conned by believing this?