I have never heard it before, however it probably means something along the line of one of my sayings. My greatest wisdom is my deepest silence.
The meaning of simplicity is the ultimate sophistication can be understood this way. Take the unit in math, from it all of mathematics is derived. Or if grammar were taught today on what some great philosophers understood, take what a definition is, it determines everything that can be asserted or denied of the subject.
Or in my own, we learn everything by listening.