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: The art of growing old is one which the passage of time has forced upon my attention.
P : One of these is undue absorption in the past.
Q : One's thought must be directed to the future and to things about which there is something to be done.
R : Psychologically, there are two dangers to be guarded against in old age.
S : It does not do to live in memories, in regrets for the good old days, or in sadness about friend who are dead.
S6: This is not always easy one's own past is gradually increasing weight.
The Proper sequence should be: