If you can't say it clearly, you don't understand it yourself
"Akrasia" [weakness of will] in rational beings is as common as wine in France.
There is no success or failure in Nature.
How do we get from electrons to elections and from protons to presidents?
The Intentionality of the mind not only creates the possibility of meaning, but limits its forms.
There are clear cases in which "understanding" literally applies and clear cases in which it does not apply; and these two sorts of cases are all I need for this argument.