One of the lessons about life's realities that can be understood from this play concerns nature of knowledge and what it is to be a genius. Both time settings in this play possess one character who can be considered to be a genius: Thomasina on the one hand and the silent Gus Coverly on the other hand. In the play, the genius of Thomasina is more fully explored, as she is shown to find proof for Fermat's last theorem and to find a formula that will capture the shape of a leaf. Yet when we think about the way in which modern day characters respond to this historical evidence of her genius, there seem to be two main approaches.
Valentine, after studying Thomasina's notebooks, still cannot bring himself to believe that they are the work of a 13 year old girl from that period of history. Note what he says to defend his incredulity:
There's an order things happen in... You can't open the door until there's a house.
For Hannah, however, genius is not about the accomplishment of incredible feats but is about a singleminded dedication and commitment to the search for kowledge. Note what she says to Valentine:
It's wanting to know that makes us matter... otherwise we're going out the way we came in.
Life's realties are therefore revealed through this discussion of genius and what it is to be a genius. Hannah argues cogently that an important reality of life is the quest for understanding and knowledge that all humans, whether or not they can be defined as "geniuses," are involved in. To be human is to search for knowledge and understanding, and it is this truth that is explored in this play.