Natural Science - Live R40 Tour

This song is about how people can forget about nature because of technology, and how we must value the Earth.

There are some odd 7/8, 6/8 and 3/4 time signatures in this song along with the normal 4/4. Rush guitarist Alex Lifeson told Songfacts: "I can pick a song that was a hard song to play and feel that was what was challenging and developed a particular style and difficult songwriting. 'Natural Science' from those days is one of those songs. Hard to play, the parts were really interesting to develop and were challenging, and the songwriting itself was a challenging experience."

Neil Peart had been tinkering with an epic song interpretation of Sir Gawain and the Green Knight. The song never panned out, but parts were later pulled out and woven into "Natural Science."