King Lear is at once the most domestic and the most philosophical of tragedies.
It quickly moves from family dispute through power politics to a consideration of quite profound ethical and metaphysical issues.
I certainly think that the statement has much in way of validity. Within the domestic realm there lies a great deal of philosophy. Shakespeare constructs a setting whereby the domestic realm holds philosophical implications. The regard between the "good" children and the "not- so- good" ones holds symbolism in terms of how human beings ascribe meaning and emotion to different elements. The fundamental issue in the play is what defines meaning. The weight that is attached to feelings is actually one of meaning. This is why the statement holds meaning in that what defines meaning becomes the central issue of the drama. When Lear says to Cordelia, "Nothing will come of nothing/ Speak again," it is a reminder that human beings are responsible for meaning in the world. Lear decides to give meaning to Regan and Goneril and discard Cordelia. In this, there is much in way of philosophy in the search for truth and meaning in consciousness. Human beings ascribe meaning to their world. The drama shows this through emotional contexts and moves into a philosophical discussion from it. In this, there is a philosophical statement being made from something so personal.