Science is about making and testing hypotheses. This is what infants do all the time! They are continually experimenting and asking “What if” in actions rather than words. The first time a baby knocks a cup from the highchair, it’s an accident. Next time, it’s on purpose to check if the falling cup will cause the same intriguing splash on the floor and the same exciting noise from mum!
As long as these little investigators are surrounded by interesting things and as long as they feel secure, they will continue to investigate and learn. Their active brains have a lot to process. No wonder they sleep so soundly at the end of the day.