Answer:c) introspection
Step-by-step explanation:
-This is the process of examining your own thoughts and feeling , looking deep within yourself without the mediation of the outside people or the outside world .
-Abstract ideas are ideas in your mind that you may have as a thought but they don't actual have any physical reality .
-So William has these ideas in his mind as he examines his thoughts and then he wrote them down as he get them so that he can bring them to reality .
-When you examine your inner ideas or abstract ideas that is an introspection .