Para-jumble (machines and life): Reorder the sentences tracing views from pre-machine definitions of life to Cartesian mechanism and modern implications. S1 = "Our ancestors thought that anything which moved itself was alive." S6 = "Therefore some scientists think that life is just a very complicated mechanism." Between S1 and S6, order the historical reasoning: P = "The philosopher Descartes thought that both men and animals were machines." Q = "But a machine such as a motorcar or a steamship moves itself; as soon as machines which moved themselves had been made, people asked, "Is man a machine?"" R = "And before the days of machinery that was a good definition." S = "He also thought that the human machine was partly controlled by the soul acting on a certain part of the brain, while animals had no souls." Choose the correct sequence of P–Q–R–S that completes the paragraph.

Difficulty: Medium

• PRSQ
• RPQS
• PSQR
• RQPS