Augustus —
Photo Credit: By Unknown - User:Bibi Saint-Pol, own work, 2007-02-08, Public Domain, https://commons.wikimedia.org/w/index.php?curid=1800667

Tiberius — cropped
Photo Credit: By Carole Raddato from FRANKFURT, Germany - Tiberius, Romisch-Germanisches Museum, CologneUploaded by Marcus Cyron, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=30158434

Caligula — Marble bust restored to its original colors. The colors were identified from particles within the marble.
Photo Credit: By G.dallorto (talk · contribs) - This file was derived from: Istanbul - Museo archeologico - Mostra sul colore nell'antichitÓ 12 - Foto G. Dall'Orto 28-5-2006.jpg, Attribution, https://commons.wikimedia.org/w/index.php?curid=44201388

Philo of Alexandria —
Photo Credit: By André Thévet - André Thevet (1502-1509): Les vrais pourtraits et vies des hommes illustres grecz, latins et payens (1584)https://archive.org/details/lesvraispourtrai01thev, Public Domain, https://commons.wikimedia.org/w/index.php?curid=12233681

Ammonius Saccas — cropped
Photo Credit: By Unknown - http://www.allposters.com/-sp/Fayum-Portrait-of-Ammonius-from-Antinoe-Encaustic-Wax-on-Linen-Posters_i1342261_.htm, Public Domain, https://commons.wikimedia.org/w/index.php?curid=63415778

Plotinus —
Photo Credit: By Anonymous - Ostiense Museum, Ostia Antica - ROME, Italy, Public Domain, https://commons.wikimedia.org/w/index.php?curid=1659353

Heraclitus — cropped
Photo Credit: By Johannes Moreelse - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=14929547

Beelzebub's Tales to His Grandson —
Photo Credit:

The body of Gurdjieff, lying in state, France —
Photo Credit: By Janet Flanner-Solita Solano papers - http://popartmachine.com/item/pop_art/LOC+1144686/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=8026196

Georges Gurdjieff —
Photo Credit: By Janet Flanner-Solita Solano papers. - https://www.loc.gov/pictures/item/95507085/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=8026263

Blavatsky's birthplace — Illustration of Yekaterinoslav, Russia Empire— now Dnipro, Ukraine—as it appeared in the early 19th century
Photo Credit: By Unknown - [1], Public Domain, https://commons.wikimedia.org/w/index.php?curid=8695071