This is interesting to me personally because Haralabos studies Philosophy (as do I). Paul, for whatever reason, probably arbitrary, has never struck me as being someone with much interest in Philosophy. Perhaps that has to do with my own misconceptions of associating idealism with philosophy, and Paul's views seem very rooted in reason and mathematics.That's all beside the point now, as I would be interested to know if Paul has similar interests (educationally) with Haralabos, and what philosophers or fields of philosophy are interesting to him.
Until the advent of modern science, mathematics was taught as a branch of philosophy. In fact, if you pursue studies in philosophy, one of the first required courses will be one in logic and reasoning (if x then y, if and only if, etc.). One analogy I have heard about the relation between mathematics and philosophy can be best described by a story a college philosophy professor told the class:A bunch of kids meet every Sunday morning to play baseball in a field in the neighborhood. There is a tree in the middle of the field that is ignored until inevitably one day a pop fly hits the tree stopping the outfielder from being able to catch it. A huge argument erupts, trying to determine whether the play should be considered an out, or an automatic double. Finally they decide its an out, and will always be an out in future situations.The argument is an exercise in philosophy (a discussion of what the rules are or should be) and the result is math (the resultant universally excepted logic).So by definition, all mathematicians are philosophers.