Everything I am talking about here takes place in the Newtonian mechanics, but it is also interesting to discuss everything in the context of special theory of relativity, quantum-mechanics or even QFT.
We say that the mass is something that measures the resistance to acceleration. In practice, in order to get the body to accelerate, we need to apply force. But want to define the force, we say that the 1N of force measures the needed force in order to accelerate the 1kg body with the acceleration $1 \frac{m}{s^2}$. Thus we completed the loop - in order to define the acceleration, we need the force and in order to define the force we need the acceleration.
Does that mean that we need to define the mass and force simultaneously? If you think about it, the concept of mass, historically speaking, was very intuitive and known in the ancient times and they could also measure it (using balance scale for example). Force on the other hand, even though very intuitive did not have any way to be measured in the ancient times. Only after the Newton's second law $F = ma$ we finally get the formula that permits us to measure the force (and maybe even define it quantitatively? ). Going back to my question, I want to find out if we can define the mass and the force before introducing the Newton's second law?
