Who was the guiding principle behind the fourteen points?

This one is too easy - the Google search popped up over 1 million hits in this search, but a history book would tell you the same. This is so basic, you should not even be asking but getting it yourself. Woodrow Wilson.

8 January, 1918:
President Woodrow Wilson's Fourteen Points
It will be our wish and purpose that the processes of peace, when they are begun, shall be absolutely open and that they shall involve and permit henceforth no secret understandings of any kind. The day of conquest and aggrandizement is gone by; so is also the day of secret covenants entered into in the interest of particular governments and likely at some unlooked-for moment to upset the peace of the world. It is this happy fact, now clear to the view of every public man whose thoughts do not still linger in an age that is dead and gone, which makes it possible for every nation whose purposes are consistent with justice and the peace of the world to avow nor or at any other time the objects it has in view.

We entered this war because violations of right had occurred which touched us to the quick and made the life of our own people impossible unless they were corrected and the world secure once for all against their recurrence. What we demand in this war, therefore, is nothing peculiar to ourselves. It is that the world be made fit and safe to live in; and particularly that it be made safe for every peace-loving nation which, like our own, wishes to live its own life, determine its own institutions, be assured of justice and fair dealing by the other peoples of the world as against force and selfish aggression. All the peoples of the world are in effect partners in this interest, and for our own part we see very clearly that unless justice be done to others it will not be done to us. The programme of the world's peace, therefore, is our programme; and that programme, the only possible programme, as we see it, is this:

It goes on to state the Fourteen Points, which you can access from the following:

President Woodrow Wilson's Fourteen Points

Fourteen Points - Wikipedia, the free encyclopedia