 What is the significance of the conference that Dr. Lessing is invited to?
Lessing nodded at Dorffman and stepped into an adjoining room with him. And now, as the book approached publication date, Lessing wondered if he would ever really get back to work again. It bore the letterhead of the International Psionics Conference: Dear Dr. Lessing: In recognition of your position as an authority on human Psionic behavior patterns, we would be gratified to schedule you as principle speaker at the Conference in Chicago on October 12th. And the more they struggled, the thicker and more impenetrable the bramble bush became— But now David Lessing had discovered a pathway through that jungle, a theory to work by— At his elbow the intercom buzzed. "I want to hear this fairy tale you're about to publish in the name of 'Theory'," Melrose said.
 It serves as an opportunity for Dr. Lessing to publicize his book
 Invitations are the primary source of imposter syndrome for scientists in this field  It shows that Dr. Melrose has more control in the field that we realize  It offers a chance for Dr. Lessing to get feedback on the parts of his theories he's not certain of  It serves as an opportunity for Dr. Lessing to publicize his book