Intercourse works well: manners and taste are shared: good sense and even talent grow insensibly... It is a great art to agree with others. The alternation of contraries beautifies and sustains the world... by joining extremes the more effective middle way is found.
Baltasar Gracián, 1647 (tr. Joseph Jacobs, 1892)
The seventeenth century explained it through the humours; ours can drop the mechanism and keep the finding: temperaments are standing biases, and a person alone is stuck with his own. The cautious see every risk and miss every window; the bold see every window and miss every cliff. Joined, they do not average into mediocrity, they correct into judgment: each extreme catches what the other cannot see, and the effective middle way emerges from the argument, not from either party. This is the deliberate version of what good marriages and great partnerships do by luck: choose your complement, on purpose, and build the arguing into the design.
Practice
- Name your own standing bias first (maxim 69's weather chart); your ideal partner is whoever is reliably wrong in the opposite direction.
- In every venture, staff the counterweight formally: the optimist's plan reviewed by the appointed pessimist, and both titles respected.
- Protect the friction; complementary pairs drift toward comfort by converting or avoiding each other, and either drift dissolves the value.
Use this when
- Use this choosing co-founders, deputies, and committees; likeness is pleasant and expensive, difference is irritating and profitable.
- Use it at home consciously; most households already contain the pair, and naming the roles turns quarrels into governance.
Ignore this when
- Don't pair opposites on values; the complement is for temperament and skill, while integrity must match exactly (maxim 116 vets that layer).
- Don't outsource your weak side entirely; the brake who never learns any engine remains half a driver.
A picture of it
The two founders annoyed each other into a company. She wanted every feature tested twice; he had shipped things from his phone at weddings. Alone, her caution had produced five perfect unlaunched projects, and his boldness three fast public failures. Their investors' favourite ritual was watching them argue, because the survivors of those arguments, plans slowed by exactly one round, launches early by exactly one quarter, kept being right. At the funding announcement, asked the secret, they answered in unison and by accident: "adult supervision", each pointing at the other.
Alone you are a bias with legs. Paired against your opposite, you are almost a judgment.