"the Path of the Just" is smaller than its author which means that the author had to minimize his greatness and write the book in a manner that is understandable and attainable by people like us so when he says that this is something that experience will prove he knows what he's talking about because he has attained these levels the Vilna Gaon himself was a Torah giant, he was born slightly after the death of the Ramchal and the Gaon of Vilna told his students (every moment was precious to this man) there are many stories about how the Gaon of Vilna valued his time there were many great people in Israel, but not all of them were referred to as "Gaon" (genius) so he told his students, if the Ramchal was alive today, I would walk by foot from Vilna till Padova (city in Italy) just to thank him for the book and return home it is not in his honor that I should come to him by carriage, I would walk to him! just to thank him for his contribution so he says this is something that experience will prove the Ramchal has merited to attain these high spiritual levels and this should be a lesson for every man to know that with effort, he can attain 