A Letter to a Friend (written 1656; published posthumously in 1690), by the 17th century philosopher and physician Sir Thomas Browne is a medical treatise of case-histories and witty speculations upon the human condition.
The Scarlet Letter | My Best Friend's Wedding | Dear John letter | White-letter Hairstreak | Letter-winged Kite | Letter of Majesty | Rupert Friend | Rob Friend | Our Mutual Friend | National Letter of Intent | letter | Identification friend or foe | Funeral for a Friend | Cliff Friend | Your Friend the Rat | What a Friend We Have in Jesus | Owen Friend | Our Mutual Friend (1998 TV serial) | National Association of Letter Carriers | My Best Friend’s Wedding | My Best Friend | Diamonds Are a Girl's Best Friend | Chi (letter) | Beta (letter) | Barons' Letter, 1301 | Whenever I Call You 'Friend' | The Johns Hopkins News-Letter | Strawberry Letter 23 | My Letter to George | Moe Letter Blues |
There were replies from Charles Chauncy of Boston, in A Letter to a Friend, dated 10 December 1767, and in a Letter to Ewer himself, by William Livingston, governor of New Jersey, in 1768.
In a letter to a friend written from Germany, Rizal expressed his feelings against the public presentation (the use as exhibits) of live Igorots in the Madrid exposition of 1887.