@Drek

I have read at least 10 people on this site that know better answers, but since no one has responded, here is my attempt:

Possibly Keynes? John Maynard Keynes I think (I always hear the term Keynesian economics). He is long dead but I think he championed the idea that government should spend during economic downturns (I am sure he is famous for more than that, but my brain can only take in so much economics).

After that it gets tricky because Liberals are far more divided on many issues (based on my experience anyway?). I could say Chomsky, but I think socially he is more libertarian...but I think many liberals fit that description, so maybe he is good. Also, I am thinking of conservative vs liberal from a modern American perspective. I am not sure that exactly aligns with liberal / conservative in Europe; and I know that some of yesterday's liberal views can become today's conservative views.

I just realized, if Ron Paul counts on conservative side, can't we just say Bernie Sanders or Barrack Obama as representing liberal positions? Notice Obama and Sanders are examples of liberals being somewhat different.

For constitutional interpretations, just look up supreme court cases you are familiar with. You will get both the majority ruling and the dissidents reports (there is a specific name for the losing side's rebuttal, but I am drawing a blank). Then you can decide which views are liberal or conservative (or even better, just view the individual ideas based on their merits and choose your stance on each issue - if we look at every issue are any of us purely conservative or liberal?)

Hope there is something useful in there somewhere, but I only named very famous people...sorry if not much help.

ZBT

Well, I used to watch YouTube videos by Owen Jones and by Russell Brand. (Yeah, yeah, haters gonna hate). But now I pretty much only use YouTube to watch stuff like cringe compilations.

"Democracy Now" is a left-leaning news channel, and Richard Wolff from "Democracy at Work" is a left-wing economist who makes YouTube videos about the current economic situation and criticized capitalism. They're not well known, as far as I know, and I cannot judge whether their arguments are particularly good.

Who do the Liberals look up to historically for economics, interpretation of the Constitution, rights, stuff like that.

Milton Friedman is to Conservative as ______ is to Liberal. — Drek

Historically, John Kenneth Galbraith. More recently, Paul Krugman.

Somehow new topics sometimes drop down the list so fast I don't notice them. Like this one.

Chomsky provides some excellent and insightful analysis into how media, politics, and government work. I haven't read Chomsky recently, but Manufacturing Consent: The Political Economy of the Mass Media is a 1988 book by Edward S. Herman (1925-2017) and Noam Chomsky is very good. His book is available for free as a PDF. If the topic interests you, you might want to investigate Edward S. Herman as well.

Necessary Illusions: Thought Control in Democratic Societies from 1989 by Chomsky concerns political power using propaganda to distort and distract from major issues to maintain confusion and complicity, preventing real democracy from becoming effective. The title of this book borrows a phrase from the writings of Reinhold Niebuhr. Sounds like another useful book.

I've been at several Chomsky talks [not recently, he's quite old now, 90+) and he is a very clear consistent thinker. His last published work was in 2016 and 2017. There is a film from 1992, Manufacturing Consent, available on YouTube. Quite good.

Who Rules America by ‎G. William Domhoff is excellent. First published in 1967 it has been updated half a dozen times over the years, so the title is not out of date. The basic idea, though, hasn't changed since 1967.

The Power Elite by C. Wright Mills 1956. Mills calls attention to the interwoven interests of the leaders of the military, corporate, and political elements of society and suggests that the ordinary citizen is a relatively powerless subject of manipulation by those entities. The book might be 60 years old, but the way the power elite works is, you know, pretty much the same from decade to decade.