I’m a fan of tolerance.  But Nathan Smith, one of the smartest people I’ve ever taught, is not.  Nathan:

As for tolerance, it is subject to this paradox: that a society
cannot be tolerant without being intolerant of intolerance. To see why,
imagine a society where 95% of the population is highly tolerant both of
homosexuals, and of violence against homosexuals. Gay people in this
society can take pleasure in the knowledge that the vast majority of
their fellows look upon their lifestyles with perfect equanimity, and do
not judge or condemn them in the least. Alas, the tolerant majority
looks with the same equanimity on a small minority of self-appointed
divine avengers of sodomy and perversion. When such thugs attack a
homosexual in the street, the crowds will not sympathize, but will
reflect that, after all, who are they to judge? How can they condemn the
sincere expression of someone else’s ethical beliefs? Clearly such
tolerance is hardly worth having…

American society today is intolerant of aggression; of racism; of
proposals for ethnic cleansing; of the Inquisition; of fascism and
communism; of polygamy. It harbors a propensity to lash out against
“sexism,” even though this word does not, as far as I can tell, refer to
any actual coherent concept, but means whatever a person who chooses to
be offended wants it to mean at a given moment. Some parts of American
society are becoming intolerant of the idea that marriage necessarily
refers to an attachment between a man and a woman. I regard some of
these intolerances as bad, but to regard intolerance in general as bad
doesn’t fundamentally make sense. You can’t really even make a coherent
distinction between moral progress and intolerance of the moral evils
that moral progress overcomes…

Once I asked, “What country has ever suffered from cosmopolitan tolerance run amok?”  Nathan has an answer:

…I would name the Roman Empire. There,
the many nations of the ancient Mediterranean met and mingled,
promiscuously exchanging myths and gods and cults and light
philosophical ideas and goods and slaves. They called it the Pax Romana,
but it was a time when Roman republican liberty surrendered to the
tyranny of the Caesars, and the intellect atrophied and descended
gradually into mediocrity. Of course, the late Roman Empire wasn’t
entirely tolerant as we mean the word. Thousands of Christian martyrs
died gruesome deaths merely for refusing to engage in the nominal
emperor-worship which the rest of the population indifferently and
ironically engaged in. But principled religious toleration hadn’t been
invented yet. The Roman Empire acted to defend the civic unity expressed
in the imperial cult, but its general attitude was one of tolerance,
of live and let live. It tolerated a labyrinth of religions and cults,
it tolerated prostitution, it tolerated social practices like slavery
and infanticide.

Like most English words, “tolerance” is somewhat ambiguous.  Some people use the word as Nathan does, to indicate blanket indifference or moral agnosticism.  But I doubt this is the standard use of the word.  Return to Nathan’s hypothetical: A gang physically attacks a gay man.  A bystander pulls his gun and tells them to back off.  Morality aside, it seems linguistically odd to accuse the bystander of “intolerance.”

If tolerance does not (normally) mean blanket indifference or moral agnosticism, what does it mean?  Libertarians may be tempted to equate tolerance with not violating people’s rights to person and property.  But this too seems linguistically odd.  Picture a homophobe who spends every day peacefully denouncing gays as disgusting and vile.  Though he never commits violence or tampers with their property, he’s clearly “intolerant” as we normally use the word.

What then do we normally mean by “tolerance”?  As a matter of common linguistic usage, something like: Not strongly opposing what people (especially strangers) do with their own person and property.  Libertarianism says, “People have a right to do what they want with their own person and property.”  Tolerance says, “People shouldn’t get too upset about what other people do with their own person and property.”  Tolerance is weaker than outright approval, but it does set a cap on disapproval.  Contrary to Nathan, tolerance in this sense doesn’t merely allow tolerance of intolerance; it implies it!  A tolerant man doesn’t fret too much when X peacefully but vociferously disapproves of Y.

Note: On this definition, there is nothing intolerant about condemning,
say, nationalists for supporting immigration restrictions.  A supremely tolerant person could still
say, “I’ll stop attacking nationalism once nationalists become a politically impotent minority.”

Whether or not I’m right about standard usage of the word “tolerance,” I consider tolerance in this sense morally good – and a worthy part of the libertarian penumbra.  Once you accept your duty to physically leave other people alone, it is also a good idea to mentally mind your own business.  Why?  Many reasons, starting with:

1. People’s moral objections to how other people use their own person and property are usually greatly overstated – or simply wrong.  Think about how often people sneer at the way others dress, talk, or even walk.  Think about how often people twist personality clashes into battles of good versus evil.  From a calm, detached point of view, most of these complaints are simply silly.

2. People’s moral objections to how other people use their own person and property often conflate innocent ignorance with willful vice. 

3. People’s best-founded moral objections to how other people use their own person and property are usually morally superfluous.  Why?  Because the Real World already provides ample punishment.  Consider laziness.  Even from a calm, detached point of view, a life of sloth seems morally objectionable.  But there’s no need for you to berate the lazy – even inwardly.  Life itself punishes laziness with poverty and unemployment.  The same goes for drunkenness, gluttony, and so on.  Such vices are, by and large, their own punishment.  So even if you accept (as I do) the Rossian principle that a just world links virtue with pleasure and vice with pain, there is no need to add your harsh condemnation to balance the cosmic scales.

4. The “especially strangers” parenthetical preempts the strongest counter-examples to principled tolerance.  There are obvious cases where you should strongly oppose what your spouse, children, or friends do with themselves or their stuff.  But strangers?  Not really.

5. Intolerance is bad for the intolerant.  As Buddha never said, “Holding onto anger is like drinking poison and expecting the other person to die.”  The upshot is that the Real World punishes intolerance along with laziness, drunkenness, and gluttony.  Perhaps this is the hidden wisdom of the truism that “Haters gonna hate.

None of these arguments are airtight.  Moral arguments rarely are.  Yet these arguments are enough to establish a strong moral presumption in favor of what English speakers normally mean by “tolerance.”  Mild disapproval of how others live their lives and spend their money is fine.  But you should not dwell on the failings of strangers.