Copying and modifying a default theme

Question

I would like to create a new theme for ggplot that is based on theme_bw().

I imagine the following steps are necessary (in pseudocode):

Answer 1

For the newer versions, based on the article here

txt <- element_text(size = 14, colour = "black", face = "plain")
bold_txt <- element_text(size = 14, colour = "black", face = "bold")

theme_whatever <- function(base_size = 14, base_family = "Palatino")
{
  theme_bw(base_size = base_size, base_family = base_family) +
  theme(
    legend.key = element_blank(), 
    strip.background = element_blank(), 

    text = txt, 
    plot.title = txt, 

    axis.title = txt, 
    axis.text = txt, 

    legend.title = bold_txt, 
    legend.text = txt ) 
}

Note that I use txt and txt_bold to avoid writing same stuff over and over again.