to not listen to, look at, or pay attention to

Extremely ignorant, completely clueless.

in Catholic moral theology, ignorance that a person could remove by applying reasonable diligence in the given set of circumstances

(baseball) Catcher's equipment

(theology) Ignorance beyond the individual's control and for which, therefore, he/she is not responsible before God.

A lack of knowledge results in happiness; it is more comfortable to not know certain things.

(idiomatic, law) A decision in bad faith to avoid becoming informed about something so as to avoid having to make undesirable decisions that such information might prompt.

plural of argument from ignorance

A fallacy where a proposition is assumed to be true because it has not yet been proved false, or vice versa.

(chiefly Wikimedia jargon) It is acceptable to break rules in situations where it is beneficial not to follow them.