In each question, the first and the last sentences of the passage are numbered S1 and S6 respectively. The rest of the passage is split into four parts. These four sentences are jumbled. Read the sentences and identify their correct and logical order.

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S1: Man has existed for about a million years.
P: Science, as a dominant factor in determining the beliefs of educated men, has existed for about 300 years; as a source of economic technique, for about 150 years.
Q: When we consider how recently it has risen to power, we find ourselves forced to believe that we are at the very beginning of its work in transforming human life.
R: In this brief period it has proved itself an incredibly powerful revolutionary force.
S: He has possessed writing for about 6,000 years, agriculture somewhat longer, but perhaps not much longer.
S6: What its future effects will be is a matter of conjecture, but possibly a study of its effects hitherto may make the conjecture a little less hazardous.
The Proper sequence should be: