How would a logician answer the schoolboy’s question, “Does your mum know you’re gay?”
The tradition of logic — attempting to formalise and systematise philosophy and reasoning — which produces such a way of speaking is infinitely more varied and interesting than many people realise. And it often creates ambiguous cases.
Take, for example, the statement, “The current King of France is bald.” Is this statement true or false? In a sense, it’s neither. It’s what’s known as an exponible statement, and it’s seemingly impossible to answer. So how might a logician deal with such a case?
Everybody uses the language of logic in everyday conversations. “That’s valid.” “That doesn’t follow.” “You’re being inconsistent.” But what do these terms really mean, and are we using them correctly?
Why aren’t contradictions allowed? What happens if we allow them? Is truth and falsity a set of exclusive, binary options or more of a sliding scale?
I’m joined today by Joe Folley, from the YouTube channel Unsolicited Advice, to answer these questions and more.
TIMESTAMPS:
0:00 - What is Logic?
5:04 - Aristotelian vs Stoic Logic
12:47 - How Logic Provides Clarity
18:42 Ambiguities in Logical Language
29:07 - Validity vs Soundness in a Logical Argument
39:40 Why Anything Follows From a Contradiction
47:42 - The Law of Non-Contradiction
56:27 - What is Truth and Falsity in Logic?
58:36 - Does Your Mum Know You’re Gay?
1:05:05 What is Fuzzy Logic?
01:08:14 - What is Modal Logic?
01:13:40 - Informal Rules of Logic
01:29:15 - Resources to Learn About Logic
