one's own judgement (judgment); decision made without consulting others; arbitrary decision
dogmatism
独断で契約を結ぶのは危険だ。
Making a contract on one's own judgment is risky.
上司の独断に部下が反発した。
Subordinates objected to the boss's arbitrary decision.
独断と偏見で物事を決めてはいけない。
You shouldn't decide things based on prejudice alone.