A question

What can I know?

Where does knowledge come from, how far does it reach, and what should we do when certainty is unavailable?

7 perspectives

  1. Socrates

    Athens

    The unexamined life is not worth living

    “The unexamined life is not worth living.” — Plato, Apology 38a
  2. Plato

    Athens

    Reality has two levels: fleeting appearances and eternal Forms

  3. René Descartes

    France → Netherlands

    Doubt everything that can be doubted; keep only the indubitable

  4. Al-Ghazali

    Tus, Persia

    Sense-perception and reason both deceive; certainty needs another ground

  5. David Hume

    Edinburgh

    Reason is, and ought only to be, the slave of the passions

    “A wise man proportions his belief to the evidence.” — Enquiry Concerning Human Understanding, §10
  6. Immanuel Kant

    Königsberg

    The mind actively structures experience; we know things as they appear

  7. Ludwig Wittgenstein

    Vienna → Cambridge

    The limits of my language mean the limits of my world

    “The limits of my language mean the limits of my world.” — Tractatus Logico-Philosophicus §5.6