Both Uses

implicit
in
The Tipping Point
(Edited)

Wegner argues that when people know each other well, they create an implicit joint memory system — a transactive memory system — which is based on an understanding about who is best suited to remember what kinds of things.
Chpt 5 *

implicit = understood (without having been directly said)
But we know, implicitly, where to go to find the answers to our questions — whether it is up to our spouse to remember where we put our keys or our thirteen-year-old to find out how to work the computer or our mother to find out details of our childhood.
Chpt 5 *

implicitly = without question or doubt

Definitions:

(1) (implicit as in: not explicitly but implicitly)
not stated directly, but understood (or capable of being understood) from something else

Shared information is often divided into two categories: That which is said explicitly (directly in words that leave no room for confusion or doubt) and that which is said implicitly.
(2) (implicit as in: implicit problem with the design)
exists as an inseparable part or characteristic
(3) (implicit as in: I trust her implicitly.)
without question or doubt
(4) (meaning too rare to warrant focus)
Another sense of the form implicitly is "without doubt or reserve" as in, "I trust Sue implicitly".

It is a more strongly stated sense of the more general meanings; e.g., "Sue implies trustworthiness," or "trustworthiness is inherent in Sue."