Why should scientists base their investigations on observations and data instead of opinions?

Scientists should base their investigations on observations and data because empirical evidence provides a reliable foundation for drawing conclusions and making informed decisions. Opinions can be subjective and influenced by biases, while data is objective and can be independently verified. By relying on measurable and reproducible results, scientists ensure that their findings are grounded in reality, which enhances the credibility and reliability of their work. This approach also fosters a systematic understanding of natural phenomena and promotes progress in scientific knowledge.