India's diverse multicultural society and tradition of tolerance is its greatest strength, and will be the basis of the country's economic strength in future, former RBI Governor Raghuram Rajan said on Thursday."Our greatest strength comes from being a tolerant, open society," Rajan said at the release here of his book "I do what I do", which is based on the speeches he delivered as the Reserve Bank of India (RBI) Governor during 2013-16."This tolerance and openness will be our greatest economic strength in future, especially given the kind of service and innovative economy we want to be," he said."We should be extremely careful not to lose this...definitely there are threats to tolerance...Eternal vigilance is the price to pay for liberty," he added.Rajan's comments come in the backdrop of the nationwide outrage and protests over the murder of journalist-activist Gauri Lankesh in Bengaluru earlier this week.Elaborating on the issue, Rajan, the only RBI Governor since Independence who did not have his term renewed by the government, said: "Every authoritarian regime comes to a turning point when it has to answer the question of how to increase growth."In 2015, a lecture Rajan had delivered as RBI Governor created controversy because of his reference to the growing intolerance in the country.