You should first pay attention to the two symetrical parts of the subject and the central link joining them.( greater -brighter // freedom/ happiness)
Define the ambivalence of the word freedom ( man without any constraint versus to abide the law of reason ( Kant)
try to find out what the presupposed thesis is freedom is akin to happiness,which could be the starting point of your development
Try to define and develop what is meant by greater freedom , the philosophical idea hidden . the two comparative forms greater brighter entail the notion of progress ( Man is working towards MORE X cf Hegel or COMTE dialectics and positivism..)
afterwards tackle the linking part necessarily lead to; I suppose you've noticed the significance of the adverb here.