An Amazon reviewer complains about John Gray's little book on Liberalism:
Finally, I think Gray could have mentioned (at least once?) that women, and slaves in the US and European colonies, were initially excluded almost entirely from the liberal project.
My passing, perhaps bloggable, thought is that this "initial exclusion" tends to be treated as an oversight. All we do is redefine "all men are created equal" to include, first, all men, and then those other, female "men" as well. Nothing fundamental here, just shaking the scales from our eyes.
The more interesting possibility, of course, would be if this oversight were more than just an oversight; if there were something about liberalism that actually explained why it was so slow to catch onto the implications of its own program.
Another book by Gray may indirectly suggest an answer. (Note that, thanks to modern technology, we no longer need to read books; we can just read about them on Amazon. Something similar, n.b., happened with Kant's "reading" of Hume, as well as Kant's hypothesis that the Milky Way is our own galaxy.)
In any event, the other book by Gray simply reminds us of a familiar divagation in liberalism, judging by its (back) cover:
... John Gray argues that liberal thought has always contained two incompatible philosophies. In one, liberalism is a theory of a universal rational consensus, which enables the achievement of the best way of life for all humankind. In the other, liberalism is the project of seeking terms for peaceful coexistence between different regimes and ways of life.
How much of the bias in liberalism is due to the uneasy suspicion of the "universally rational" that a single way of life wouldn't work so well outside the sphere of white European (bourgeois) men? If you're defining your project in terms of universal consensus, and some groups seem to have goals that are incompatible with your own, then the temptation is to label those troublemakers as "irrational." Which is pretty much how it went.
We are now somewhat more prepared to admit that women, blacks, etc. might be "rational" after all ... not without some disparagement of "reason" in the first place that itself may have a whiff of sour grapes about it. But the modus-vivendi school of liberalism seems potentially more inclusive.