your introduction should state the reasons why you disagree with the author - i do see a bit here and there but they should be together. Also the main body paragraph is a bit of a mess. You state the primary reason but the rest of the paragraph you don't really state secondary reason explicitly but just jump on it. I think it is better to follow a format like "First of all, secondly, finally" - at least make your new reasons obvious to the reader. I would also expand the reasons/examples a bit - at current state it is like 2 sentences per reason - they should be fleshed out a little more.
The ghandi example i am not so sure of - ghandi did spend his life "his own way" - no one forced him to do what he did. Sure he had hardships but he chose that path thus it is "his own way".
I am not sure if your conclusion starts at "In sum" or "In many fields". If it is "In many fields" you shouldnt really introduce new ideas but you should just reiterate your body paragraphs. You should also mention what the author stated not just "the mentioned definition".
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