In Chapter 5 of his book, Homo Deus: A Brief History of Tomorrow (2017), Yuval N. Harari treats all modern -isms (Communism, Conservatism, as types of religions, defined as: "anything that confers super-human legitimacy on human social structures. It legitimizes human norms and values by arguing that they reflect super-human laws. Religion asserts that we humans are subject to a system of moral laws that we did not invent and that we cannot change.... Other religions, from Buddhism and Taoism to Nazism, Communism and Liberalism, argue that the super-human laws are natural laws and not the creation of this or that god. Of course, each believes in a different set of natural laws discovered by different seers and prophets, from Buddha and Lao Tze to Hitler and Lenin."
He might (or might not) be right about the others, but what he writes is decidedly untrue of small-l liberalism. Liberalism emerged, with science, from the Enlightenment, as a challenge to the cruelties of imposed dogmas, both earthly and sacred. Only a few schools of thought (e.g., libertarianism) within the large tent known as liberalism, have sought to replace the old dogmas with new ones designed to promote some teleology (in the case of libertarianism, maximal individual liberty). Libertarians believe in natural law; many other liberals do not. Thus, natural law cannot be taken as a necessary tenet of liberalism, as Harari casually surmises. Liberalism has no teleology - no goal, purpose or end for which humans should strive. It has no unique story of the "good life." Indeed, liberalism is defined in large measure by its refusal to tell people how they should live. To promote a unique story of the "good life" would be counter-liberal or illiberal.
Liberals strongly disagree among themselves about the respective roles of public- and private-ordering in society. Progressive Liberals, such as John Dewey and John Rawls, believe the government should play a large role in countering the inequities of private markets. Conservative Liberals, such as David Hume and F.A. Hayek, believe that governments should play as little a role in society as possible to minimize coercion of individuals. Still other Conservative Liberalism, like Edmund Burke, allowed a broader scope for government action, in accordance with a polity's history and culture. Moderate Liberals, like J.S. Mill and Karl Popper, tend to agree with Conservative Liberals that government failures are costly and that government coercion should be limited, but also agree with Progressive Liberals that government has an important role to play, for example in preventing majoritarian biases from disadvantaging minorities. As I wrote a couple of years back in an article in AEON with my friend and colleague Aurelian Craiutu, a society in which liberal rights are guaranteed only for some members cannot truly be said to be a liberal society. Moderate Liberals acknowledge the propensity for both market- and government-failures, and view public policies as experiments from which we might learn, over time, what works better (not necessarily best) for an "open" society. They can only ever be experiments because the humans who devise them, like the rest of us, are fallible. While a Conservative Liberal might conclude from this that we should not conduct such experiments, Moderate Liberals (let alone Progressives) are not so squeamish, on grounds that the status quo ante is not necessarily better, and failed policies can be replaced by better policies (as well as by no policy at all).
It is worth noting that in his list of "seers and prophets," Harari does mention any liberal thinker. Was it just an oversight? Or did Harari realize that it would have highly misleading to use those terms to describe Adam Smith or the other liberal thinkers I have named. None of these scholars purported to establish a socially-imposed moral dogma. All of them favored an "open" system of social order that did not impose on individuals one and only one acceptable way to live. Aside from a canonical form of the golden rule (e.g., "do not do unto others what you would not have them do unto you"), which exists in Mill's "no harm" principle, they were ecumenical about individual life choices.
Far from a religion, Liberalism stands for the absence of any form of super-human legitimacy for social order.