There's a strong liberalist tradition on the left. For instance, Chomsky considers libertarian socialism (anarchism, left-wing communism, etc) as the "later elaboration" of classical liberalism. Sees libertarian socialists as the serious inheritors of the classical liberal tradition. http://www.pentaside.org/article/chomsky-govt-in-the-future.html
"... Marx sees the revolutionary more as a frustrated producer,
than as a dis-satisfied consumer. And this, far more radical,
critique of capitalist relations of production, flows directly,
often in the same words, from the libertarian thought of The
Enlightenment. For this reason, I think, one must say that
classical liberal ideas, in their essence though not in the way
they developed, are profoundly anti-capitalist. The essence of
these ideas must be destroyed for them to serve as an ideology of
modern industrial capitalism."
> Lots of them do. That's not a reason to give up on liberalism. No
> one has proposed anything better than competitive elections,
> universal suffrage, extensive civil and political liberties, and
> democratic decisionmaking that is relatively neutral on deep values
>
> -- and (more controversially here) in economics, no one has proposed
> a plausible alternative to a mixed economy, where that means one
> that combines large elements of markets and planning (whether or not
> it involves private property and wage labor), at least in the
> "interim"; like the next 300 years. (Long enough for me!) But
> please, let's not get derailed by that because I am not going to
> defend this proposition. I just note that it is one on which Yoshie,
> Doug, and I all agreed pretty recently.
I think plausibility is little guide. Had I been told about today's economies, without having had any real experience with it, I probably would've found it implausible, unworkable.
For instance, I conceivably might've argued that trade was impossible due to barter's overhead, not thinking about the money abstraction.
Tayssir