Portraits of Humanists

Geoffrey Chaucer
From the Illustrated Magazine of Art, p. 9. This looks a little bit like some (but not all) of the early portraits of Chaucer I've seen reproduced, but is best considered, I believe, as a mid 19th century interpretation of what Chaucer ought to have looked like. I could be quite wrong, of course, as I'm certainly no authority on portraits of Chaucer. It does show up (same portrait, different scan) in at least one professor's online Chaucer page.

It is worthwhile (and fun!) to read Chaucer in the original rather than in "translation."

Desiderius Erasmus
Portrait by Hans Holbein, from Hans Holbein le jeune: L'œuvre du maitre.
Identified as: "Longford Castle, Comte de Radnor" from 1523
Here are several other portraits of Erasmus from the same source:
Bâle, Musée Municipal (1523, writing, no background)
Paris, Louvre (1523, writing, with background)
Parme, Galerie (1530, with book)
Bâle, Musée Municipal (undated, circular)
New York, Metropolitan Museum (undated)
Paris, Walter Gay, (undated, "D'après le Portrait de Longford Castle")
Hampton Court (undated, "D'après le Portrait de Longford Castle")
St. Pétersbourg, Ermitage (undated, with closed book)
Besançcon, Museée ("Copie d'après le Portrait de Parme")

Here is a different digitization of the portrait identified above as "Paris, Louvre." It is from the Perry-Castañeda Library Portraits.

Oliver Goldsmith
From the Illustrated Magazine of Art, p. 17. "Drawn by Gilbert. Engraved by J. Linton."
He looks splendidly grumpy.

Hans Holbein
From Hans Holbein le jeune: L'œuvre du maitre. Identified as "Bâle, Musée," 1523-1524. I presume that this must be a self-portrait.
Here are two other self-portraits, identified as such, from the same source:
Florence, Offices (1543)
London, Wallace Collection (undated, circular)

Dr. Samuel Johnson
From the Illustrated Magazine of Art, p. 16. "Drawn by Gilbert. Engraved by J. Linton." Here is the full original engraving, showing "Dr. Johnson reading 'The Vicar of Wakefield.'"

Here is a different portrait. It is from the Perry-Castañeda Library Portraits.

Samuel Finley Breese Morse
An artist? Yes.
From Bolton, facing p. 202.

Sir Philip Sidney
From the frontispiece of Great Englishmen of the Sixteenth Century.