Why your concern for the future affects your actions.
The human brain has been called the most complex object in the known universe, and in many ways it's the final frontier of science. A hundred billion neurons, close to a quadrillion connections between them, and we don't even fully understand a single cell.
Parenting is the ultimate long-term investment. Be prepared to put far more into it than you get out of it, at least for some time. Given the stresses of contemporary American culture, the happiness of couples plummets the minute they become parents.