The twenty best things I found in my regular blogs in the month of December. For the ~ninety best things, see Part I and Part II.

• A.Critch | Why I Want Humanity to Survive -- A Holiday Reflection -- I find myself entirely in agreement with Critch's reasons.
• The Moral Character of Cryptographic Work, h/t Schneier on Security -- why academic cryptographers cannot ignore the dimension of political power in their work (and a model for scientists everywhere in re-evaluating the moral character of their respective fields).
• Popehat | Talking Productively About Guns -- incredibly important, at least if you want your rhetoric to change minds.
• Interfaces of the Word | left materialism for 2016 -- ought to be required reading for anyone hoping to make the world better via liberal reform.
• What Refugees Ask When They Arrive in Europe, h/t Marginal Revolution
• Read and compare: Hillary Clinton and Bernie Sanders's plans to "rein in Wall Street". See also economist Larry Summers's response to Sanders's proposal, in which he shows that even terrible university presidents can make excellent economists.
• Minding Our Way | Obvious Advice, as in "Have you tried just following the...?" and Minding Our Way | Moving Towards the Goal, as in "The only thing that there is to it is..."
• Calls to (realistic) action: Thing of Things | We Can Be Heroes and Jaibot | The Thing You Can Change.
• On the other hand, important for some people to hear: Thing of Things | Against Moral Obligation.
• GatesNotes | The Top 6 Good-News Stories of 2015, but on the other hand Slate Star Codex | How Bad Are Things?
• Slate Star Codex | Should AI be Open? -- It seems that this is the question begged by initiatives with names like "Open AI", and yet, no one is bothering to ask it? Odd.
• Unsong, Scott Alexander's foray into webserial fiction.
• Unequally Yoked | The Opposite of Kicking People in the Shins -- Leah Libresco tells the story of her conversion from a rationalist atheist to a rationalist Catholic, and in the process expresses the propositional claims of Catholicism with less inferential distance to my understanding of the world than I have heard anywhere else.
• Aleteia | The Little Way of Terry Pratchett -- Libresco on Pratchett on morality; simultaneously charming and thought-provoking.
• Calvin and Muad'Dib is the excellent Calvin and Hobbes/Dune mashup that you didn't know was missing from your life. "People, not commercial organizations or chains of command, are what make great civilizations work..."

Bonus mathy best-of:

• The Problem of Indignation Bot, Part 1, 2, 3, and 4 -- An incredible brainteaser about AIs playing the Prisoner's Dilemma while reading each others' source code.
• Shtetl-Optimized | Ask an unbounded question, get an uncomputable answer -- on the uncomputability of 10,000-dimensional (infinite) physics.