CF Dictionary · Decision Making
Qualitative Difference
A difference of kind, not of degree. CF treats qualitative differences as the things that matter in evaluation.
A qualitative difference is a difference of kind, not degree. "Has wheels" vs. "doesn't have wheels" is qualitative. "Has 4 wheels" vs. "has 6 wheels" is quantitative.
Why CF cares
CF focuses on qualitative differences because:
- They're breakpoints. Quantitative changes become qualitative at breakpoints.
- They're dimension-crossing. Different dimensions are qualitatively different.
- They're what goals care about. Goals are usually about kinds ("does it work?", "is it safe?"), not degrees ("how much does it cost?").
- They enable pass-fail evaluation.
Examples
- Alive vs. dead. Qualitative.
- Working vs. broken. Qualitative.
- Celsius 99 vs. 100. Quantitative.
- Celsius 36 vs. 37. Quantitative but at the breakpoint of "fever or not".
- $1000 vs. $5000. Quantitative.
CF's epistemic commitment
"CF offers an approach to thinking and decision making focused on qualitative differences not quantitative factors."
This is one of CF's most distinctive methodological commitments. CF refuses to reduce everything to degrees and then weight them.
"Qualitative, notable, important, meaningful differences — differences that connect to some kinda relevant intellectual concept — are sparse and rare." — criticalfallibilism.com