Another year, another set of great things to read! You may remember that when I started this, I linked to e-versions of the works but link rot attacked that list pretty quickly. Now I'm linking to online versions. The e-reader versions are easily available and fairly cheap so you can still go that route.
Aeschylus: Prometheus Bound link
Herodotus: The History (book VII-IX) link
Thucydides: The History of the Peloponnesian War (book I-II, V) link
Plato: Statesmen link
Aristotle: On Interpretation (Chapters 1-10) link
Aristotle: Politics (book III-V) link
Euclid: Elements (book I) link
Tacitus: The Annals link
St Thomas Aquinas: Summa Theologica (part I-II QQ 90-97) link
Chaucer: Troilus and Cressida link
Shakespeare: Macbeth link
Milton: Paradise Lost link
Locke: An Essay on Human Understanding (Book III, Ch 1-3, 9-11) link
Kant: Science of Right link
Mill: Representative Government (Ch 1-6) link
Lavoisier: Elements of Chemistry (Part I) link
Dostoevsky: The Brothers Karamazov (Part I-II) link
Freud: The Origin and Development of Psycho-Analysis link
There are a couple of things that I want to mention with this list. The first is that the size of each month varies pretty widely for year three. I did the best I could in portioning. If you're planning on reading along this year, you may want to work ahead at times. The meatiest part of the year is going to be September and October. All four pieces will require some effort.
The other thing is that there are some wonderful bits of history and literature here. We're getting more Herodotus and some Thucydides. Tacitius is basically history. We've got Shakespeare, Chaucer and Dostoevsky coming up. Some absolutely wonderful reads.
Hope you come along!