SELECT member_name FROM member WHERE party_id  =  3 INTERSECT SELECT member_name FROM member WHERE party_id  =  1
Which member names are shared among members in the party with the id 3 and the party with the id 1?
[Schema (values) (types)]: | party_people |  region : region_id (text) , region_name (number) , date (text) , label (text) , format (text) , catalogue (text) | party : party_id (text) , minister (number) , took_office (text) , left_office (text) , region_id (text) , party_name (text) | member : member_id (text) , member_name (number) , party_id (text) , in_office (text) | party_events : event_id (text) , event_name (number) , party_id (text) , member_in_charge_id (text);