Aren't you, in fact, criticizing it - the "Theory Left" - right now? Isn't that what TaraElla consistently does? And don't people, like me, respond? So 1) it can be criticised, and 2) that criticism is accepted to the extent counter-arguments are formulated.

I really don't know what to make of the rest of what you've written: "The problem is that while following the pattern of reason at times, it threw away the foundations of reason."?

What does that even mean? You, perhaps tellingly, don't claim that *reason* itself has been abandoned, but rather its "foundations". Is this a tacit omission that you do accept reason is employed by the "Theory Left", but the background, foundational "classical" liberal assumptions and precepts are not - and that's your issue? The latter if which you would no doubt have a harder time defending with rational argumentation, and instead just hope that they are presumed by everyone.

Well, I'm sorry, they're not. In reality the highly historically-contingent and particular liberal worldview is rejected by most of humankind. I always liked Stuart Hampshire - a liberal - on this. He understood that these "foundations" of which you speak have always been quite controversial:

"It is not only possible, but, on present evidence, probable that most conceptions of the good, and most ways of life, which are typical of commercial, liberal, industrialised societies will often seem altogether hateful to substantial minorities within these societies and even more hateful to most of the populations within traditional societies … As a liberal by philosophical conviction, I think I ought to expect to be hated, and to be found superficial and contemptible, by a large part of mankind."