One reason is that say someone is on bed rest/in the hospital not allowed to move, it can make them very week and make it very hard for them to walk again.
Speak about how the world has evolved through the topics of science and technology (separately)
Discuss the fact that 40 years ago computers weren't invented and now they are beyond the capacity of a human brain.
Discuss how science nowadays has been able to uncover mysteries of the earth as well as how science has created (in cooperation with technology) robots.
Basically discuss how it has changed over the years, the importance of technology in the changing world as well as science.
I think it means that the person feels elated and peaceful
