Ideas...

For if you are caught up in ideas, then you will be caught up in the
self. And even if you are caught up in ideas about nothingness, you
will still be caught up in the self. That's why we should not get
attached to the belief that things either exist or do not exist. This
is the hidden meaning when I say that my teachings are a raft to be
abandoned when you see true being.

Diamond Sutra