Galileo studied problems in five steps: asking questions, guessing hypotheses, mathematical reasoning, experimental verification, reasonable inference and drawing conclusions.

When Galileo studied the law of falling body, he first questioned Aristotle's point of view when encountering problems, and then guessed that falling body was the simplest variable-speed movement, and the simplest variable-speed movement was that the speed change was uniform. Then he experimented, Galileo made mathematical reasoning on the experimental results, and then made reasonable extrapolation to draw a conclusion.

Galileo's contribution:

Galileo was the first scientist to introduce experiments into mechanics. He determined some important mechanical laws through the combination of experiment and mathematics. 1582, after long-term experimental observation and mathematical calculation, he got the isochronous law of pendulum, and then dropped out of school at 1585 because of family financial difficulties. When he left the University of Pisa, he deeply studied the works of ancient Greek scholars Euclid and Archimedes.

He wrote his first paper entitled "Balance" based on the principle of lever and buoyancy. Soon after, he wrote a paper on gravity, which revealed the essence of gravity and center of gravity for the first time and gave an accurate mathematical expression, so he became famous at one fell swoop. At the same time, he questioned many viewpoints of Aristotle.