Pre-socratic Philosophers (+ Plato & Socrates
- Thales: presocratic, explaining reality, made of water, first to take philosophical approach
- Anaximander: presocratic, reality was boundless
- Anaximenes: presocratic, air is the source of things, similar to Thales
- Empedocles: presocratic, matter was made up of the 4 elements
- Heraclitus: presocratic, reality is changing
- Democritus: western materialism, everything consists of atoms and empty space
- Pythagoras: influential math thinker, believed everything derived from numbers
- Xenophanes: presocratic, suggested one god who was not anthropomorphic, or a god who did not imitate human qualities.
- Parmenides: presocratic, change is an illusion, founded Eleatic school
- Zeno of Elea: presocratic with Parmenides, change is an illusion
- Gail Stenstad: feminist philosopher, anarchic thinking
- Victor Frankl: a Jewish philosopher who saw humans as ultimately free beings
- Mohandas Gandhi: jain philosopher, knowledge predates senses