A title that sounds like poetry, and a subtitle that seems to contradict
the title! But the subtitle is right, and originally it was just the
title. A strange subtitle, isn't it? Preface to a Science of
Mathematical Education. All sciences - in their prenatal stage - have
known this kind of literature: only the term used was not 'Preface',
but, for instance, 'Prolegomena', which * means the same though it
sounds less provisional. In fact such works were thicker than the
present one, by up to ten times. There is much more that can be said
about a science before it comes into being than after; with the first
results comes modesty. This is the preface to a book that will never be
written: not by me, nor by anybody else. Once a science of mathematical
education exists, it will get the preface it deserves. Nevertheless this
preface - or what for honesty's sake I have labelled so - must fulfil a
function: the function of accelerating the birth of a science of
mathematical education, which is seriously impeded by the unfounded view
that such already exists. Against this view I have to argue: it rests on
a wrong estimation - both over and under estimation at the same time -
of what is to be considered as science.