18.1 The language of thinking
First, let’s talk about how we think. On the most basic level, our knowledge about the world is stored in propositions. In a mathematical sense, a proposition is a declaration that is either true or false. (In binary terms, true is denoted by 1 and false is denoted by 0.)
“The sky is blue.”
“There are infinitely many prime numbers.”
“1 + 1 = 3.”
“I got the flu.”
Propositions are often abbreviated as variables such as A = ”it’s raining outside”.
Determining the truth value of a given proposition using evidence and reasoning is called inference. To be able to formulate valid arguments and understand how inference works, we’ll take a quick visit to the world of mathematical logic.
18.1.1 Thinking in absolutes
So, we have propositions such as A = ”it’s raining outside” or B = ”the sidewalk is wet”. We need more expressive power: propositions...
