Plato.

Wonder is the feeling of a philosopher, and philosophy begins in wonder. Theaetetus (155d)

The dialogues below are ordered thematically. Starred dialogues “*” are of disputed authenticity

First Tetralogy
Euthyphro What is piety (holiness)?
Apology Socrates trial defense speech
Crito Should one disobey unjust laws?
Phaedo Is the soul immortal?
Second Tetralogy
Cratylus Are proper names conventional?
Theaetetus What is knowledge?
Sophist What is a sophist?
Statesman What is a statesman?
Third Tetralogy
Parmenides What is a Platonic Form?
Philebus What is pleasure?
Symposium What is love? What is poetry?
Phaedrus What is rhetoric? What is love?
Forth Tetralogy
Alcibiades I* Socrates and Alcibiades
Alcibiades II* Ignorance, Ambition and Power
Hipparchus* What is the desire (love) of gain (philokerdēs)?
Lovers*
Fifth Tetralogy
Theages*
Charmides What is temperance (self-control)?
Laches What is courage?
Lysis What is friendship (philia)?
Sixth Tetralogy
Euthydemus Logic and Informal Argumentation
Protagoras What is rhetoric? What is virtue? Can virtue be taught?
Gorgias What is rhetoric? What is virtue? Can virtue be taught?
Meno What is virtue? Meno's Paradox. Can virtue be taught?
Seventh Tetralogy
Hippias Major* What is it for a thing to be fine?
Hippias Minor Is it better to lie involuntarily or voluntarily?
Ion What is the origin of art and poetry?
Menexenus A funeral oration
Eighth Tetralogy
Cleitophon Is Socratic elenchus mere exhortation?
Republic What is a just state or society? What are the aims of education?
Timaeus Universe order and origin
Critias The Myth of Atlantis
Ninth Tetralogy
Minos* What is a just law?
Laws What laws should a just society have?
Epinomis* What is wisdom?
7th Letter* Biographical; 7th letter: the limits of philosophical writing
Apocrypha
Eryxias* Is wealth necessary for virtue and happiness?
Definitions*
Epigrams*