Time and causation flow in one direction only, and so does logic, and we must be careful not to make errors in direction.

In that situation the key would be to change someone’s mind about that core principle rather than anything else.

A implies B. B is implied by A. • If A then B. B if A.

The primary aim of normal language is communication, whereas the primary aim of logical language is to eliminate ambiguity.

soundly but starting from different basic beliefs. So two people can both be logical but still disagree about things.

for now it’s important to note that the grey area should be included somewhere, otherwise we’re just ignoring part of reality.

The idea of logic is to have clear rules so that conclusions can be drawn unambiguously and consistently by different people.

logical explanations need to be independent of personal experiences.

The key is to remember that it is both statements “A” and “A implies B” that together allow us to infer statement B. So if statement B is not true it is either because A isn’t true or because “A implies B” isn’t true. The possibility of the implication being untrue is often overlooked.