Philosophy, with the sources left on
Read carefully. Then test whether you did.
CritThinker is a library of sourced quotations and a practice gym for nine reasoning skills. Famous lines are labelled when they are loose translations, doubtful, or simply not theirs.
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Streak
One quotation, a short review, then four questions on the skill that needs the work. About five minutes. One missed day a week does not break the streak.
“By art is created that great Leviathan called a Commonwealth, which is but an artificial man.”
Thomas Hobbes · Leviathan, introduction
Optional reading
Optional reading
Stoicism in 5 steps
Five short Stoic exercises, using only lines this library already files.
Optional reading
Spot fallacies in the news
Six common moves in headlines and arguments, each with the reply the card already gives.
Optional reading
Thinking clearly about risk
Five habits that make rare events, small samples, and first numbers feel larger than they are.
Reading lists
Nietzsche quotes explained
The Nietzsche lines this library files, with the work, the translator, and the attribution left on.
Stoic quotes
Lines from Marcus Aurelius, Seneca, Epictetus, and Zeno of Citium, grouped by the theme the card actually carries.
Stoic quotes for anxiety
Stoic cards in this library about fear, imagination, and the judgement added to events.
Marcus Aurelius quotes from Meditations
Every Marcus Aurelius line in this library comes from Meditations. The citations name the section.