“If you think your political beliefs are simply based on ‘common sense’ or ‘practicality,’ you’re probably not digging deep enough.” From its first sentences, Arguments for Liberty, edited by Aaron Ross Powell and Grant Babcock of Lib​er​tar​i​an​ism​.org, challenges readers to examine what they believe about politics and morality, and why — in other words, to practice philosophy.

Arguments for Liberty features nine philosophers, making nine different cases for why political liberty is the most moral and just system — from more common arguments, like utilitarianism or the argument from natural rights, to less widely known theories like Kantianism, objectivism, Rawlsianism, and moral pluralism. “Regardless of how many — if any — of the book’s chapters you find compelling,” the editors write, “our goal is to inspire you to continue your study of ethics and libertarianism.”

Arguments for Liberty takes readers everywhere from ancient Athens, exploring Aristotle’s Nicomachean Ethics, to 20th-century America, discussing John Rawls’ A Theory of Justice. The book provides not only an excellent introduction to libertarianism, but also a crash course in some of the most important and influential political and ethical theories in history. You don’t need to have a philosophy background to read the book, and each chapter is designed to stand on its own, to be read in any order.

This work is important, Powell and Babcock write, for two reasons: first, because freedom matters. And second, because philosophy matters — particularly in order to defend freedom. Without knowing our first principles, our reasons for supporting freedom, we cannot effectively make the case for it. And even if you ultimately disagree with all nine theories presented, they write, this exercise is still beneficial — understanding the source of libertarians’ differences among themselves helps draw into focus what we all agree on, as well as areas where we should sharpen our arguments against critics.

Human Freedom Index
The 2016 Human Freedom Index, co-published by the Cato Institute, the Fraser Institute, and the Liberales Institut, measures freedom around the world based on a broad measure that includes personal, civil, and economic freedom. It is the most comprehensive freedom index so far created for a globally meaningful set of countries, covering 159. The index shows that measuring worldwide freedom is complex — since 2008, we have gained economic freedom worldwide but lost some personal freedom, leaving the score roughly unchanged. Most countries had changes in their ratings, with about half increasing in freedom and half decreasing. The top 10 jurisdictions were Hong Kong; Switzerland; New Zealand; Ireland; Denmark; Australia, Canada, and the United Kingdom tied for sixth place; Finland, and the Netherlands. The United States, meanwhile, ranked all the way down in 23rd place. The most significant backsliders were China, Russia, and Turkey. The index finds a strong correlation between human freedom and democracy, while countries in the top quartile of freedom have significantly higher incomes per capita.