reading this made me chuckle a little, because it reminded me of the following:
which reminded me of a famous quote from the aforementioned Alfred North Whitehead:
The safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato.
so, when i am reading:
it would seam to me that, yes, the suggestion would appear to be incorrect, but more importantly the suggestion would also seam to lead one into very tedious disputes about who said what first, who read whom when, who acknowledges to have been influenced by whom in what way and to what extend, etc. 
now,… i am not saying that to give credit where credit is due isn’t important,… but i do think that very often it is much more important what one makes ( out ) of an idea, rather than the idea itself. 