This page summarizes principles and guidelines for understanding the world, in particular how to evaluate claims made in politics, by advertising and the news media, and by religion, science, and pseudo-science.

These principles fall into roughly three groups: logical fallacies, often used in politics and in casual arguments, that have been recognized for centuries; cognitive biases, recognized and understood mostly in recent decades by modern psychology; and perceptual illusions, ways in which what we perceive is not accurate, some venerable but others also recognized only recently. These are followed by some heuristics that are useful for avoiding these pitfalls, and some conscious correctives to adopt to counter them.

Logical fallacies

These are familiar rhetorical gambits like ad hominem, straw man, false dilemma, appeals to fear or ignorance, genetic fallacy (i.e. if so-and-so said it, it can’t possibly be true), slippery slope, circular reasoning, and “tu quoque” (i.e. “you too” and recently “but what about—“ [e.g. Hillary’s emails]).

Resources with details and examples at

These are all routinely observed especially in political debates. When you detect these, they are usually evidence that there is no legitimate case to the argument. (E.g., if your rhetoric is merely to insult people, via schoolboy nicknames, you haven’t made any kind of argument about the issue at hand, and likely you’re admitting you don’t have a legitimate argument.)

Cognitive biases

These were abstruse just a couple decades ago but more and more are working their way into public consciousness. These include confirmation bias, anchoring, the Dunning-Kruger effect, in-group bias, the sunk cost fallacy, and many others.


Perceptual illusions

These include pareidolia, the tendency to see kittens in clouds and the Virgin Mary in a tortilla (, and general issues from the basic principle that our senses are contextual — we perceive reality not as it “truly is” (whatever that means), but in the context of what surrounds the things we perceive. Famous recent example: the blue dress (, whose colors varied by the viewer, and many optical illusions ( about color, shape, and size.

Another is the inability of humans to appreciate enormous numbers, including long spans of time.


These are ‘rules of thumb’ that often work but are not guaranteed to work. ( Some of these overlap with the cognitive biases, e.g. the availability bias (, the tendency to draw conclusions based on examples close to hand. (The notorious application of this is to conclude the world is going to pieces because of all the crises seen on the evening news. The corrective is to understand why the evening news shows you only the crises, and how these crises are infinitesimal samples of everything that occurs around the world each day.)

The most famous heuristic is Occam’s razor (, the notion that of all possible explanations, the simplest one is mostly likely true. But the rule doesn’t *guarantee* the simplest explanation is true.


  • Understand how and why the media works.
  • Understand how and why advertising works.
  • Understand methods for drawing conclusions and testing them and correcting when necessary.
  • Understand why “good people” can disagree about politics and religion, and these disagreements are not about right and wrong, good or evil. (c.f Moral Foundations Theory, and Jonathan Haidt’s The Righteous Mind.)
  • Understand what sources in the media, or from among experts, can be trusted, and why others might be biased — e.g. understand the Media Bias Chart and beware relying on extreme sources on either side.
  • “Follow the money” — who benefits? who loses? This explains much political debate, which isn’t about principles, but about who’s trying to gain personal or financial advantage. “It is difficult to get a man to understand something when his salary depends upon his not understanding it,” which entirely explains the organized opposition (by special interest groups) to the recognition of climate change.
  • Understand, through examples of civics, and from ideas of engineering and project management (considering how no large project, private or government, is ever finished to budget and schedule), how complex the world truly is, and thus why virtually all conspiracy theories are implausible.

Motto: Be skeptical, but not cynical. Be savvy.

Commandments and Moral Guidelines

The Biblical Ten Commandments can be disregarded. The first several of them are admonitions to worship a particular god in the context of a polytheistic environment. (And they in no way form the basis for the US Constitution or American law in general.) The rest are commonplace edicts found in cultures throughout history—they were not invented by the writer of the Ten Commandments, as if such strictures had never occurred to anyone before God handed them down—and in fact form part of what Alex Rosenberg has called the “Core Morality” that has evolved precisely because it allows collectives of human to cooperate in groups, and thrive where masses of selfish individuals would not. Ironically, some of the reasons people reject evolution – because it identifies humans as just another animal species among millions that have lived and mostly died across billions of years – arise because of the sense that humanity, and especially one’s own tribe, is ‘special’, a sense that exists precisely because of evolution. Humans survive by human nature, which is a self-serving gloss on the actual world.

In contrast, thinkers in recent decades have put forth more sensible, noble sets of principles (or commandments), often handily distilled into lists of ten. Here are the best ones I’ve found.

Michael Shermer, THE MORAL ARC (2015)

A Provisional Rational Decalogue (pp180-185)

  1. The Golden Rule Principle: Behave toward others as you would desire that they behave toward you.
  2. The Ask-First Principle: To find out whether an action is right or wrong, ask first.
  3. The Happiness Principle: It is a higher moral principle to always seek happiness with someone else’s happiness in mind, and never seek happiness when it leads to someone else’s unhappiness through force or fraud.
  4. The Liberty Principle: It is a higher moral principle to always seek liberty with someone else’s liberty in mind, and never seek liberty when it leads to someone else’s loss of liberty through force or fraud.
  5. The Fairness Principle: When contemplating a moral action imagine that you do not know if you will be the moral doer or receiver, and when in doubt err on the side of the other person.
  6. The Reason Principle: Try to find rational reasons for your moral actions that are not self-justifications or rationalizations by consulting others first.
  7. The Responsibility and Forgiveness Principle: Take full responsibility for your own moral actions and be prepared to be genuinely sorry and make restitution for your own wrongdoing to others; hold others fully accountable for their moral actions and be open to forgiving moral transgressors who are genuinely sorry and prepared to make restitution for their wrong-doing.
  8. The Defend Others Principle: Stand up to evil people and moral transgressors, and defend the defenseless when they are victimized.
  9. The Expanding Moral Category Principle: Try to consider other people not of your family, tribe, race, religion, nation, gender, or sexual orientation as an honorary member equal to you in moral standing.
  10. The Biophilia Principle: Try to contribute to the survival and flourishing of other sentient beings, their ecosystems, and the biosphere as a whole.

Reduced to just one:

Try to expand the moral sphere and to push the arc of the moral universe just a bit farther toward truth, justice, and freedom for more sentient beings in more places more of the time.


Writer Adam Lee, The New Ten Commandments

  1. Do not do to others what you would not want them to do to you.
  2. In all things, strive to cause no harm.
  3. Treat your fellow human beings, your fellow living things, and the world in general with love, honesty, faithfulness and respect.
  4. Do not overlook evil or shrink from administering justice, but always be ready to forgive wrongdoing freely admitted and honestly regretted.
  5. Live life with a sense of joy and wonder.
  6. Always seek to be learning something new.
  7. Test all things; always check your ideas against the facts, and be ready to discard even a cherished belief if it does not conform to them.
  8. Never seek to censor or cut yourself off from dissent; always respect the right of others to disagree with you.
  9. Form independent opinions on the basis of your own reason and experience; do not allow yourself to be led blindly by others.
  10. Question everything.


Lee Bayer & John Figdor, A Secular Ten Non-Commandments (discussed here,

  1. The world is real, and our desire to understand the world is the basis for belief.
  2. We can perceive the world only through our human senses.
  3. We use rational thought and language as tools for understanding the world.
  4. All truth is proportional to the evidence.
  5. There is no God.
  6. We all strive to live a happy life. We pursue things that make us happy and avoid things that do not.
  7. There is no universal moral truth. Our experiences and preferences shape our sense of how to behave.
  8. We act morally when the happiness of others makes us happy.
  9. We benefit from living in, and supporting, an ethical society.
  10. All beliefs are subject to change in the face of new evidence, including these.


Sean Carroll, THE BIG PICTURE: On the Origins of Life, Meaning, and the Universe Itself (2015). (Discussed here.)

Ten Considerations:

  1. Life isn’t forever. (And that’s what makes it special; eternity would be boring.)
  2. Desire is built into life. (From desire comes caring, and our potential to choose to make the world a better place.)
  3. What matters is what matters to people. (The universe doesn’t care. But we care about it, and ourselves.)
  4. We can always do better. p422b:

    We nevertheless make progress, both at understanding the world and at living within it. It may seem strange to claim the existence of moral progress when there isn’t even an objective standard of morality, but that’s exactly what we find in human history. Progress comes, not from new discoveries in an imaginary science of morality, but from being more honest and rigorous with ourselves…

  5. It pays to listen. (Don’t ignore whatever wisdom might be found in the ancient religions, just because their ontology is obsolete.)
  6. There is no natural way to be. (We are unavoidably ‘natural’, but nature is not a guide.)
  7. It takes all kinds.

    Much of what has been written about the quest to lead a meaningful life has been produced by people who (1) enjoy thinking deeply and carefully about such things, and (2) enjoy writing down what they have thought about. Consequently, we see certain kinds of virtues celebrated: imagination, variety, passion, artistic expression. .. But a fulfilled life might alternatively be characterized by reliability, obedience, honor, contentment… The right way to live for one person might not suit someone else.

  8. The universe is in our hands. (At one level we’re all just physics and chemistry, but at another level we’re capable of reflection and making decisions about how to behave.)

    We won’t be able to stave off the heat death of the universe, but we can alter bodies, transform our planet, and someday spread life through the galaxy.

  9. We can do better than happiness. (Is a pill to be perfectly happy the ideal goal? Life is a process, and perhaps a life is better characterized by its achievements than how happy it was.)
  10. Reality guides us. (Beware mental biases that aren’t true but make you happy. It takes effort, but it’s worth it.) p427:

    We have aspirations that reach higher than happiness. We’ve learned so much about the scope and workings of the universe, and about how to live together and find meaning and purpose in our lives, precisely because we are ultimately unwilling to take comforting illusions as final answers.


One more, slightly cheeky list, from Christopher Hitchens, here.