For John Stuart Mill (1806-1873), a good reason to reject Christianity and Islam is hell belief, and in his Autobiography he recalls his father’s strong views on the matter:
[H]is aversion to religion, in the sense usually attached to the term, was of the same kind with that of Lucretius: he regarded it with the feelings due not to a mere mental delusion, but to a great moral evil. He looked upon it as the greatest enemy of morality: first, by setting up factitious excellencies,–belief in creeds, devotional feelings, and ceremonies, not connected with the good of human kind,–and causing these to be accepted as substitutes for genuine virtues: but above all, by radically vitiating the standard of morals; making it consist in doing the will of a being, on whom it lavishes indeed all the phrases of adulation, but whom in sober truth it depicts as eminently hateful.
God is eminently hateful because He threatens non-followers with hell and sends them there. So Mill writes:
I have a hundred times heard him [my father] say, that all ages and nations have represented their gods as wicked, in a constantly increasing progression; that mankind have gone on adding trait after trait till they reached the most perfect conception of wickedness which the human mind could devise, and have called this God, and prostrated themselves before it. This ne plus ultra of wickedness he considered to be embodied in what is commonly presented to mankind as the creed of Christianity.
Why did Mill’s father regard the Christian idea of God the pinnacle of wickedness? Mill explains:
Think (he used to say) of a being who would make Hell–who would create the human race with the infallible foreknowledge, and therefore with the intention, that the great majority of them were to be consigned to horrible and everlasting torment.
This is most particularly a Calvinist conception of hell, but the general point is made. And Mill himself looked forward to a time when all Christian churches would abandon belief in a hell-fire creating and sending deity:
The time, I believe, is drawing near when this dreadful conception of an object of worship will be no longer identified with Christianity; and when all persons, with any sense of moral good and evil, will look upon it with the same indignation with which my father regarded it.
Did you catch the word indignation? Mill looks forward to a time when the idea of a hell-fire creating and sending deity is not just broadly rejected as a doctrine, but regarded as repugnant.
But if the doctrine of hell is so evil, why don’t more Christians fall into madness and corruption following the logic of it? Mill’s father had a theory, which is pretty plausible, and can be summarized as follows: religious training equips Christians with atrocious critical thinking skills, and, like everyone else, Christians are prone to cognitive dissonance and confirmation bias:
My father was as well aware as any one that Christians do not, in general, undergo the demoralizing consequences which seem inherent in such a creed, in the manner or to the extent which might have been expected from it. The same slovenliness of thought, and subjection of the reason to fears, wishes, and affections, which enable them to accept a theory involving a contradiction in terms, prevents them from perceiving the logical consequences of the theory. Such is the facility with which mankind believe at one and the same time things inconsistent with one another, and so few are those who draw from what they receive as truths, any consequences but those recommended to them by their feelings, that multitudes have held the undoubting belief in an Omnipotent Author of Hell, and have nevertheless identified that being with the best conception they were able to form of perfect goodness. Their worship was not paid to the demon which such a Being as they imagined would really be, but to their own ideal of excellence.
In other words, Christians are not really Christians. They generally direct their worship to a deity that is far better than the one actually given to them by their priests–and that’s a good thing.
But wait. We’re now in the 21st century. How goes it with hell belief, at least in the United States, since Mill’s Autobiography was published in 1873? Here’s a Gallup poll summary from 2004:
From 1997 to 2004, belief in hell has ranged between 56% and 71%. The 2004 data reveal that 70% of Americans overall believe in hell, while 12% are not sure and 17% do not believe in hell. Again, the percentage is much higher among regular churchgoers: 92% of those who attend weekly believe in hell, as do 74% of those who attend nearly weekly and just half (50%) of those who attend church seldom or never.
Belief in hell varies only somewhat among other demographic categories, although likelihood to believe is somewhat lower across the board than was the case for heaven. With regard to political orientation, 83% of Republicans say they believe in hell, vs. 69% of Democrats and 58% of those who say they are independent. Americans with a high school education or less are slightly more likely to believe in hell than those with at least some college education (77% to 65%).
And a Harris poll from December 2013 puts hell belief at 58% of Americans. So this is where we’re at–a long way from Mill’s dream of hell belief treated as a barbarity; as a source for indignation.