Solutions A belief that something is true based on a feeling rather than evidence has 5 entries with similar clues

• 8-letter words
• a-prioriReasoning from first principles (Latin)/reasoning based on theory rather than observation
• credenceBelief in something as true
• 9-letter words
• empiricalBased on observation rather than pure logic
• 13-letter words
• discretionaryBased on personal decision rather than on regulations
• rule-of-thumbA fairly accurate guide based on practice rather than theory