gerassapience
"The wisdom of old age" or "advanced-years wisdom." I coined this word as a watchword in my published doctoral dissertation on the subject: "A Biblical Theology of Gerassapience" (Peter Lang, 2010). The word is a combination of the Greek word for old age (geras) and the Latin word for wisdom (sapientia = sapience).
John Doe displays "gerassapience" in his answer to the question (noun). The statement by John Doe has a "gerassapient" value (adjective).