Often called the "first true scientist," he established the cycle of observation, hypothesis, experimentation, and verification. He rejected Greek authority, stating: "The seeker of truth is not one who studies the writings of the ancients and places his trust in them..."

Jabir moved chemistry from mystical alchemy to an experimental science. He wrote: "The first essential in chemistry is that you should perform practical work and conduct experiments, for he who performs not practical work nor makes experiments will never attain the least degree of mastery."

Al-Biruni emphasized the need to remove human bias from scientific observation. He introduced the concept of repetition—repeating an experiment multiple times to calculate an average and eliminate outliers or errors.

In The Canon of Medicine, Ibn Sina laid down 7 rules for testing new drugs. He insisted that drugs must be tested on humans (not just animals), in pure form, and across different disease stages to prove efficacy.

Muslim scholars developed the practice of Isnad (chain of transmission) in Hadith studies to verify sources. This rigor was applied to science, creating the first system of academic citation and referencing to credit original authors.

The Scientific Method requires precise data. Muslim engineers invented sophisticated astrolabes, quadrants, and balances capable of measuring tiny fractions, allowing for data-driven science rather than guesswork.