On April 11, 2026, our group of four continued our exploration of Steven Pinker’s Rationality. In this discussion, we distinguished formal fallacies by detecting violations of the rules of deductive reasoning through analysis, and informal fallacies that may have a valid form but are psychologically compelling and intellectually dishonest. The informal fallacies include:
The straw man fallacy is when someone distorts, exaggerates, or misrepresents an opponent's argument to make it easier to attack. An example is creating a rationale for military action that excludes contrary trusted threat assessments.
Begging the question is circular reasoning, not answering the question. For example, "Life on Earth must have started with a microbe from another world because living organisms can only originate from extraterrestrial sources." This conjecture does not answer the question of how life began.
Whataboutism is a rhetorical tactic used to deflect criticism by making a counter-accusation or raising an unrelated issue that shifts the focus, such as when a reporter asks a politician about a specific scandal, and he responds, "Why are you asking me about that when my opponent has a much worse record on an entirely different issue?"
An appeal to authority is when someone claims a statement must be true simply because an expert said so, rather than providing actual evidence, such as when someone cites Linus Pauling’s claims of the power of Vitamin C to prove that high doses of this vitamin can cure major diseases like cancer.
Guilt by association is when someone claims a person or an idea is bad or wrong simply because they are linked to a disliked person, group, or ideology. For example, dismissing the link between smoking and lung cancer simply because it was extensively researched by Nazi scientists is a classic case of guilt by association.
An example of an appeal to emotion is the appeal to fear, like when George W. Bush argued, "Facing clear evidence of peril, we cannot wait for the final proof—the smoking gun—that could come in the form of a mushroom cloud." It created a false urgency, since later reports confirmed that the underlying intelligence about Iraq's nuclear capabilities was incorrect.
The gambler's fallacy is the mistaken belief that if a random event happened more frequently than usual in the past, it is more likely to happen in the future. The random rewards schedule gives rise to expectations that one’s luck will change and is the most difficult to extinguish. A person will keep pulling a slot machine lever long after the rewards have stopped.
For that matter, what is randomness? After all, we do not live in Laplace's clockwork universe based on Newtonian mechanics, and his demon, knowing the positions, speeds, and directions of travel of all particles, cannot predict future events such as the toss of a coin or the roll of a pair of dice. Quantum mechanics creates a probabilistic universe that contradicts the gambler’s belief that he will always win the next round. The game of poker bridges Laplace's determinism and true randomness. It is a game of incomplete information, where you use math to manage what you can know and use probability to gauge your hand’s chances of success. You can bet on your poker hand, but how well can you judge if your opponent is bluffing?
Can the structure of probabilistic events serve as the foundation for a neural network? Ludwig Wittgenstein famously raised the question of the "fuzziness" of words. He argued that many concepts have no sharp boundaries or a single essence that defines them. Wittgenstein explains that the fuzzy nature of words can be attributed to a family resemblance rather than a crisp definition. The word “game” does not have a single thing in common, but it shares a network of overlapping and crisscrossing similarities, much like how members of a family share certain features without every member having all of them. These crisscrossing similarities have high or low probabilities that correspond to strong or weak connections to certain features, respectively. Tversky and Kahneman noted that the strength of connections gives rise to the availability heuristic, in which our behavior is shaped by our experiences, as when a gambler pulls the slot machine lever and expects a winning combination. If training data can bias AI, can our training data (education and experiences) bias us?
Can we master the laws of probabilities? Is understanding probability enough to make us more knowledgeable? We invite you to find out more about Steven Pinker’s Rationality: What It Is, Why It Seems Scarce, Why It Matters, BF441.P56 2021 on May 2, 2026, from 2 PM to 4 PM.
