Alexander Bernshteyn, leading research scientist of Skoltech and IITP RAS, accepted the invitation of PostNauka editors to participate in the ‘Mathematical walks’. After the voyage, Professor Bernshteyn noted: ‘When I was offered to take part in Mathematical walks, I was really doubting, as I don’t consider myself to be significant in the actual mathematical world. But then I thought – my life story would be an example of the fact that the big desire to do math is possible to realize, and in application-oriented activities the success is usually achieved in real issues where ‘the mathematical essence’ is revealed, and the new look at this essence has often been a way to success”.