AM is right, you're being willfully ignorant of the scientific method at this point. Theories never become laws. That's not how it works. The Law of Gravity is simply the observation that objects are attracted to each other with a pull that is a function of their mass and relative distance from one another (which can be expressed as a precise equation). A theory of gravity is something like General Relativity or Loop Quantum Gravity that attempts to explain why that is the case. The Theory of General Relativity has been proven accurate repeatedly in expirements and in practical applications (again, the GPS system wouldn't work if it were wrong). Are you suggesting that since we don't call it the Law of General Relativity that it is merely a "guess"?