What do you call a person who makes the best statements in your/a group?

He says the best things, makes the smartest statements, gives the most useful information, you definitely want to listen to him when he starts talking, overall, he always says the best things and makes the best statement. In my context, it's a "he" that I'm talking about, but the word doesn't need to be gender specific.

For instance, David, who is our best sayer (?), said, "...".

So I'm thinking something like Sayer, but Sayer isn't actually a word--my criteria is usually Oxford Dictionaries. A compound word would be fine, but not a phrase.

Edit: To be clear, I am looking for a noun.

Solution 1:

Depending upon the context, there are many words which could be used here.

Laureate also fits here. A laureate is someone who has been given a very high honour because of their ability in a subject of study.

Intellectual is also possible.

An intellectual is a very educated person whose interests are studying and other activities that involve careful thinking and mental effort.

Insightful can also be used.

Adroit and adept are also good words.

Other possibilities:

• Far-sighted.
• Sapient
• Well-advised
• Sagacious
• Shrewd

Solution 2:

One possibility is "spokesperson", defined by the Cambridge dictionary as

a person who is chosen to speak officially for a group or organization

So you could write, "David, our spokesperson, said .."

Another alternative is "ambassador", defined by the Cambridge dictionary as

a person who represents, speaks for, or advertises a particular organization, group of people, activity, or brand (= type of product)