
The Art of Logic

It doesn’t make more things true, it just uncovers more true things than we saw before.
Eugenia Cheng • The Art of Logic
Time and causation flow in one direction only, and so does logic, and we must be careful not to make errors in direction.
Eugenia Cheng • The Art of Logic
The primary aim of normal language is communication, whereas the primary aim of logical language is to eliminate ambiguity.
Eugenia Cheng • The Art of Logic
If they are attempting to be logical, the first person will try to justify what they’re saying by constructing a logical argument to back it up. The second person should then either try to find a flaw in their logical argument, or try to construct their own logical argument to back up their assertion that the person is wrong.
Eugenia Cheng • The Art of Logic
Like time, logic has a direction and we must not try to violate it.
Eugenia Cheng • The Art of Logic
soundly but starting from different basic beliefs. So two people can both be logical but still disagree about things.
Eugenia Cheng • The Art of Logic
It doesn’t mean that you won’t ever try, and that nobody else will, it’s just that right now you’ve decided this is your starting point and is the basis of your logical system, or your belief system.
Eugenia Cheng • The Art of Logic
I will keep coming back to is that you can be alogical without being illogical, and indeed being alogical is unavoidable and sometimes beneficial or even crucial, whereas being illogical is undesirable.
Eugenia Cheng • The Art of Logic
A implies B. B is implied by A. • If A then B. B if A.