Category Theory Illustrated – Logic
&gt; Logic is the science of the possible. As such, it is at the root of all other sciences, all of which are sciences of the actual, i.e. that which really exists<p>I really don’t think this is right. Logic is a discipline of consistent re-writing of expressions. However, there may be (even existing) things that are not expressable to sufficient degree in finite (or even countably infinite) strings, which I think means they are outside of logic. There are definitely “possible” things that are outside of logic (because not expressable).