title: Font size change with theme() not working
body: <p>I am plotting barplots. I have written a script, however when I want to change the front size of the texts in the barplots, it does not work. For example, whether I write <code>axis.text.y= element_text(size=6)</code> or <code>axis.text.y= element_text(size=15)</code>, I have the same text size. I don't know where the problem is in my script.</p>
  
  <pre><code>p &lt;- ggplot(d, aes(x=treatment, y=value, fill=R2)) + geom_bar(stat = "identity", position="dodge")
  p &lt;- p + labs(list(title = "title", x = "xaxis", y = "yaxis"))
  p &lt;- p + scale_fill_manual(values=c(grey(0.4), grey(0.8)))
  p &lt;- p + theme(axis.text.x = element_text(size=6), axis.text.y= element_text(size=6), axis.title = element_text(size=6), title = element_text(size=4))
  p &lt;- p + geom_hline(aes(yintercept=100), lty=2)
  p &lt;- p + ylim(0,100)
  p &lt;- p + scale_x_discrete(limits=c('T','F','S', 'R'))#to reorder x axis
  p &lt;- p + theme_bw()
  p &lt;- p + theme(legend.position="none")
  p
  </code></pre>