diff --git a/make.R b/make.R
index 081014e..afb3795 100644
--- a/make.R
+++ b/make.R
@@ -15,7 +15,7 @@ if (length(args) == 0) {
     for (rmd in commandArgs(trailingOnly = TRUE)) {
         # render Rmd to PDF
         if ( grepl("\\.Rmd$", rmd) && file.exists(rmd)) {
-            render(rmd, pdf_document())
+            render(rmd)
         } else {
             print(paste("Ignoring: ", rmd))
         }