The Wexner Center has unveiled one of its biggest exhibits in honor of its 25th anniversary which includes several Picassos from Les Wexner’s personal collection. To delve into two of Picasso’s most famous nudes, art historian T. J. Clark is set to lecture at the Wex on “Nu au plateau de sculpteur” (Nude, green leaves, and bust) and “Nu au fauteuil noir” (Nude in a Black Armchair). The second painting is featured in the Wexner’s exhibit. Clark’s most recent book is titled “Picasso and Truth: From Cubism to Guernica,” and he will be doing book signings before the lecture. The event begins Tuesday at 7 p.m., the book signing is set for 6 p.m.