A.F. Chalmers, one of the best philosophers of science authored a book titled ‘What is this thing called as Science?’. Unlike the rhetoric we regularly encounter, this question has a well defined answer. Knowledge of the philosophy of science is essential to attain a better understanding of the scientific theories, discoveries and their limitations. This knowledge is pivotal for one to use their own creativity and reasoning appropriately in understanding the mysteries of the universe and there by expanding the horizons of knowledge. As students of Physics we should know how science works and let’s answer the question ‘ What is this thing called as physics?’.
R.P. Feynman uses the example of chess board to explain how science works. Imagine there are two people playing chess and you are a spectator lacking the knowledge of rules of the game. So, you sit and watch every move each of the players make trying to make out the rules of the game. A while later you see that the queen is moved one square up. Now you make an assumption, let’s call it assumption 1 which says that ‘Queen can move only one square up every time’. You continue watching the game and suddenly you see that one of the players moved the queen one square sideways. This definitely is a shocker and you immediately restate assumption 1 as ‘ Queen can move upwards and also side ways one square at a time’ and continue watching the game. Now the queen is moved 7 squares upwards and other player moved his queen 3 squares side-wards. Now assumption one is changed to ‘Queen can move upwards or side-wards with no limit on the number of squares it can move across.’
What is the spectator doing in the process? The spectator in the process of trying to figure out the rules of the game is making assumptions. The assumptions were not taken for granted but were constantly tested. When the assumptions failed to explain a particular move, they are restated to explain not just that particular move but also all the moves made till that point (in time). The spectator got closer to the actual rules of the game every time he changed them.
Physics works exactly in the same way. It is about deciphering the rules of the nature by constantly observing it. Initially the rules or laws, like those we learnt during our Physics tuition classes are made based on the observations. When ever these rules fail to explain a particular observation the rules are changed or restated to explain all the observations made so far. And in the process humanity’s understanding of the nature and its working it honed.