The discussion focuses on proving that the sum of the series 1/2 + 1/3 + ... + 1/n is less than the integral of 1/x from 1 to n, which in turn is less than the sum 1 + 1/2 + 1/3 + ... + 1/(n-1). Participants suggest that this can be understood through graphical representation, specifically by visualizing the area under the curve and the rectangles formed by the series. The integral serves as a method to approximate the series, with one approximation being an underestimate and the other an overestimate. This approach highlights the relationship between discrete sums and continuous integrals. Understanding this inequality provides insight into the behavior of harmonic series and their convergence.