Off the top of my head, strong candidates for that set are:
**“#Suffering is bad”**
That's the only thing that I'm certain is bad. My foundation for #ethics.
**“#Mathematics is true”**
Math is the only #epistemology that I trust. And math is behind everything.
**“I matter. Others matter, too.”**
This guards against the polar opposites of egotism and immolation — both mistaken.
[…]
That is what “reasoning from first principles” means to me.
The causal chain may be long sometimes, with many logical steps involved. And there is room for uncertainty and for epistemic humility. But the ultimate goal is to evaluate ideas and to make decisions reducing them all to lower-level equivalents based on a few core propositions.
To the best of my knowledge, nothing summarises best what's “good” or “bad” or “important” than **#suffering** (avoiding it, preventing it, reducing it).
Not wellbeing, pleasure, flourishing, happiness, freedom, transcendence, detachment, or love.
And nothing seems better to me to measure and describe reality, what reality could be like, and how exactly it can be changed, than **#math** (rationality, logic, science).
Its contenders all look clearly inferior: intuition, empathy, revelation, tradition, authority, serendipity, chance, art, anecdote…
“#Freedom matters”
Very often more freedom means individuals accomplish more of their stated preferences, and very often those preferences point towards less suffering for them (and sometimes for others, too).
Freedom is (usually) good because it (usually) reduces suffering. But it's not a given.
(Needless to say, this is not a justification for despots or kidnappers, who do not reduce but increase suffering.)