Numbers grew with human needs — counting led to fractions, debt led to negatives, geometry led to irrationals, and equations led to imaginaries.
Walk through
Step 1 of 5
ℕ — counting numbers
1, 2, 3, … Born from counting sheep, days and people. No zero, no negatives, no fractions yet.
Stages
- Naturals {1, 2, 3, …} — counting.
- Whole numbers {0, 1, 2, …} — add zero.
- Integers {…, −2, −1, 0, 1, 2, …} — add negatives.
- Rationals — fractions.
- Reals — add irrationals.
- Complex — add i.