Please clarify the concept of gratitude.

Gratitude is a vast concept. That I am thirsty and drink water, I would feel grateful but I think modern-day science has given man a gigantic framework of thanksgiving. For example, earlier man could only drink water and thank God for it but modern-science made it known to man that to cater to his fresh water requirements, God put in place a complete rain cycle. The original source of this water is the saltwater stored in the seas and oceans.