What is the difference between 'marxist' (with a small 'm') and 'Marxist'? This question arose to me when I came across this:
It follows from this belief that if you can totally change the 'ensemble of the social relations', you can totally change human nature. This claim goes to the heart of Marxism and of more broadly marxist (with a small 'm') thinking.
I have seen that, similarly, Daniel Dennett in his paper Postmodernism and Truth differentiates between 'Truth' and 'truth':
When philosophers argue about truth, they are arguing about how not to inflate the truth about truth into the Truth about Truth, some absolutistic doctrine that makes indefensible demands on our systems of thought.
(emphasis by me)
Maybe this is common in English and is not specific to fields like philosophy.