taking the side of the underdog

Perhaps it originates in his formative years as a poor boy in schools for rich boys, this taking the side of the underdog and loathing of the powers that crush them. He said of his youthful self, 'I was both a snop and a revolutionary. I was against all authority ... I loosely described myself as a Socialist. But I had not much grasp of what Socialosm meant, and no notion that the working class were human beings.'

(...) 

But this tendency, perhaps forged in those schools full of richer boys, to remain an outsider would keep him from being swept up during that war and ever after in what would later be called groupthink, a spinoff of the word doublething he coined in his last novel. 

- Orwell's Roses, Rebecca Solnit (2021)