Brinkley worked assiduously to join Beschloss and Doris Kearns Goodwin on the air.
Brinkley worked hard to join Beschloss and Goodwin on the air.  
mnli hypothesis: Brinkley worked hard to join Beschloss and Goodwin on the air.   premise: Brinkley worked assiduously to join Beschloss and Doris Kearns Goodwin on the air.