Is religion a mental illness?

I think the answer is yes, if we are talking about people who have sufficient reasoning capability to understand the natural universe to a degree that would prove that religion is man made... but refuse to acknowledge what they know to be true in favour of their unwavering faith.

If you can understand that religion is false but you will yourself to believe otherwise, then you are mentally ill.

It doesn't matter that 7/8ths of humanity believe in some kind of god.
It doesn't matter that only 1/7th of humanity does not believe in gods.
A majority belief in a god is not evidence of anything but the gullibility of the human race.

Religion is a mental illness that humanity is slowly curing with education.
Every scientific discovery in biology, anthropology, physics, geology, and many other scientific fields, is another bit of evidence that believers have to disbelieve.
It gets more difficult to disbelieve the ever growing evidence and if you can't disbelieve evidence, you can't believe in a god.

There's only so much rationalising a reasonable person can do before seeing the truth.
Unreasonable people are getting more upset at the "attack on religion", which is not actually an attack, but a defense of reason.
These people will not be convinced by evidence. If evidence was a punch in the face, they'd deny their own bloody noses.
These are the mentally ill that believe in something beyond all reason and evidence to the contrary.

Some of these people quietly refuse to see reason and pray in private, never talking about their religion.
I have no problems with them. Someone's belief in a god, however lacking in reason, is none of my business.

The people that must be countered are those that start trying to push religions into schools and governments, and start pushing for blasphemy laws.

These people are not satisfied to be themselves mentally ill; they want all humanity to share their mental illness.

This is where the line is drawn in the sand. Those who cross that line must be met with resistance both firm and resolute.

With reason.
With education.
With love for humanity.