There are many themes in the novel In the Time of Butterflies. Some of the more important ones include change and transformation, and courage. If you think about what those themes mean within the novel, you can gather some points that support the theme.
Alvarez focuses on the changes in the Mirabal sisters as they progress toward their revolutionary activities. This is the mean point of the theme of change and transformation. As one would expect of a book with the word butterfly in the title, transformations play a big role in the story. Alvarez shows that though change can be painful, it frequently allows individuals or even a nation to discover stronger, richer, and more courageous versions of themselves.
Finally, courage plays a big role in the themes of the novel, linking with the other two already noted above. Clearly, the Mirabal sisters are testaments to the power of courage. In Alvarez's rendering, the sisters also reveal fragility because they are not always courageous and self-assured. Their very fears make them all the more admirable. Trujillo and his men are shown as the counterpart, as the coward
Another important theme in Butterflies concerns the relationship of women's private lives to their public and more political lives. The traditional role of women in the Dominican Republic when the events of the novel take place is in the private sphere as mothers and daughters, subservient to either a husband or a father. El Jefe represents both of these in the public, political sphere, which was reserved for men. When the sisters step out of their role as daughters and mothers to become political and work against Trujillo's regime, they do more than rebel against him: they rebel against patriarchy as a social order. Repeatedly, for example, the girls' father is equated with Trujillo. Minerva finding out about her father's mistress juxtaposes with the October 12 celebration, which she calls "Discovery Day Dance." There her father encourages her to dance with the dictator to keep up appearances. Minerva says to him, "Have you lost all your principles?" In fighting against Trujillo, the women break down boundaries between private and public, trying out a new social order for women in the process.