In John Locke’s A Letter Concerning Toleration (1689) he presents two minor arguments for religious toleration, and one major one.
The 'Unchristian' argument
If the gospel and apostle may be credited no man can be a Christian without charity, and without that faith which works, not by force, but by love.
His argument goes something like this:
Premise 1 No one can be a true Christian unless they are charitable.It's valid, but P2 doesn't convince; if a persecutor thinks he is doing the persecution to help the persecutee achieve eternal life, that would surely be consistent with charitable principles.
Premise 2 Religious persecutors aren’t charitable.
Conclusion Therefore religious persecutors aren’t true Christians.
The 'Inconsistency' argument
For if it be out of a principle of charity, as they pretend, and love to men’s souls, that they deprive them of their estates, maim them with corporal punishments, starve and torment them in noisome prisons, and in the end even take away their lives; I say, if all this be done merely to make men Christians, and procure their salvation, why then do they suffer ‘whoredom, fraud, malice, and such like enormities’ which, according to the apostle, manifestly relish of heathenish corruption, to predominate so much and abound amongst their flocks and people?The suggestion is that persecutors are insincere in their charity; else they would address themselves to those with more obvious moral failings than heretics. But most Christian doctrine allows that simple belief in Christ is sufficient for salvation, not moral probity, so a persecutor could easily sidestep this argument.
The 'Irrationality' argument
…penalties are no ways capable to produce such belief. It is only light and evidence that can work a change in men’s opinions; and that light can in no way proceed from corporal sufferings, or any other outward penalties.This is Locke's major argument. The state can legislate to affect our actions, but not our beliefs. Beliefs are not the sort of thing that we can simply adopt at will (‘To believe this or that to be true is not within the scope of the will’). This is because we think our beliefs are true. If we think something is false, we cannot will ourselves to believe it. The link between belief and reality would be broken.
If beliefs cannot be adopted at will then there is no point in trying to force them. Torture could change what we say, but not what we believe.
Faith only, and inward sincerity, are the things that procure acceptance with God ... . In vain, therefore, do princes compel their subjects to come into their church communion, under pretence of saving their souls. If they believe, they will come of their own accord; if they believe not, their coming will nothing avail them.
The argument goes like this:
Premise 1 Magistrates’ only sanction is physical force.It's valid, and at first blush, the premises appear true. But note that if someone does not understand that belief cannot be coerced, then he wouldn’t be irrational. But if he knows that beliefs cannot be coerced, it is plainly irrational to persecute, per this argument.
Premise 2 Physical force cannot alter religious beliefs.
Conclusion So magistrates cannot alter religious beliefs.
Locke did allow a couple of exceptions to toleration: anyone whose religious beliefs threaten society. He cites atheists and those whose beliefs would put them in thrall to a foreign power. Atheists, because they could not be trusted to keep their word since they think there is no divine judgement!
Promises, covenants, and oaths, which are the bonds of human society, can have no hold upon an atheist. The taking away of God, though but even in thought, dissolves all.
A daft thought, as if morality is simply something that operates only through a celestial CCTV, but indicative of the contempt for atheism at the time.
Jeremy Waldron presents a counter-argument to Locke, by distinguishing between coercion by direct and indirect means, and reveals that the situation is more complicated than Locke assumed; a point first made by his contemporary Jonas Proast. The environment could be directed towards the desired end by the magistrate; for example, restricting reading material and discourse for a prisoner, thus achieving a gradual, indirect conversion.
Susan Mendus responds to Waldron's response thus:
Since coercion may therefore be applied to religious ends by this indirect means, it can no longer be condemned as in all circumstances irrational.Waldron’s claim is that by curtailing individual freedom of speech, and freedom to read what you want to read, the population’s religious beliefs could be controlled. This casts doubt on P2. Locke has overlooked the rather complex way we come to our beliefs about reality. But Locke’s argument may still apply to direct coercion, although the existence of victims of brain-washing suggest that even this coercion can be effective over time.
Susan Mendus responds to Waldron's response thus:
...the irrationality of coercing belief, even indirectly, is akin to the irrationality of brainwashing; it can certainly be done but it does not generate the right kind of belief or, more precisely, it does not generate a belief which is held in the right way.Such a belief would still not guarantee one's salvation because, ultimately, one was pushed into acquiring it. Waldron had anticipated this objection and counters that the manner in which one is led to form a belief does not alter the content of that belief. Also, consistency would demand that most of our beliefs are ruled out too, since “In most cases (not just a few), the selection of sensory input for our understanding is a matter of upbringing, influence, accident or constraint”, so an absurd conclusion follows.
Mendus's point makes sense, I think, if we are in the business of judging the 'truthiness' of beliefs; someone whose reading has been restricted to just one book is likely to have different beliefs to someone who has read widely - and it's reasonable to conclude that the more widely-read person is more likely to have true beliefs. This would not be a genetic fallacy because the sources and methodologies being considered do cast a shadow on the beliefs.
Nevertheless, Waldron’s argument hits home, because he's only concerned with what someone truly believes, not what true things someone believes. So, in light of Waldron's objection, Locke’s irrationality argument fails, although could perhaps be moderated to account for the complex way we come to acquire beliefs.
Warburton, N. (2002) Arguments for Freedom , Milton Keynes, The Open University