Exercise 3 solution

Dates used (from the Wikipedia pages in the chapter): Marx born 5 May 1818, died 14 March 1883. Weber born 21 April 1864, died 14 June 1920. The Protestant Ethic appeared 1904 to 1905.

Calculated in Python (py -X utf8):

(a) Marx at death: 64. (1883 minus 1818 is 65, but his birthday in May had not yet come by 14 March, so he was one year younger.)
(b) Weber at death: 56. This matches the figure the Max Weber page gives.
(c) 1904 minus 1883 = 21 years.

What can be said from dates alone: Weber was 18 when Marx died, so Weber could in principle have read Marx's published work, and Marx could not have read Weber's, because Weber's major writing came after Marx's death. The chapter's Conflict theories page also contrasts Weber with Marx by his emphasis on social action, which suggests Weber knew of Marx's ideas, but that is an inference, and I did not check whether Weber actually read Marx (check).

The honest limit: dates show who could have influenced whom, not who did.