"A black man isn't an object to be liked or disliked like an orange or a pear or a piece of furniture.  So why should you say, 'I like them'?

"The simple question perplexed Isnard.  He had never thought of Negroes as anything but children - often contrary children, but easily enough managed if you knew how."

Isnard has worked his entire career in close proximity to the Senegalese people.  He has a condescending attitude towards them, views them as children, but he does not feel negatively towards them.  You could say that he even has a certain affection for them.  

Doudou, however, correctly points out the flaws in this thinking.  Isnard does not see Africans as individuals, but rather as part of a total group with a stereotypical set of characteristics.   It is this reductive thinking that creates hostility - Isnard cannot even imagine why Doudou would turn down his generous terms for returning to work.  If he could think of Doudou as a thinking individual like himself, Isnard might understand that pride and dignity is more important to a person than monetary compensation.  

Could this lack of understanding work the other way as well?  Do the strikers see the French as individuals, or as a homogenous group that seeks to oppress them?