Following the advice from this question, I've tried to load Ubuntu without a graphics environment by replacing quiet splash in the grub boot script with text, and alternately by appending it to the parameters.
This hasn't worked; Ubuntu 17.10 still launched the Gnome Display Manager and shows the login screen. However can I boot Ubuntu 17.10 into a terminal interface? Thank you.
For future people: Rinzwind's systemctl command works for me, while the similar systemctl command from this previous question did not work. guiverc also points out that text as boot parameter only refers to outputting kernel messages as text, not to booting into a command line interface.