| Formation: | 1787 |
| Type: | Student debating union |
| Headquarters: | Edinburgh |
| Leader Title: | President |
| Leader Name: | A. Grut and F. Tyson |
| The Diagnostic Society of Edinburgh | |
| Size: | 150px |
The Diagnostic Society of Edinburgh is a debating society in Edinburgh, Scotland. The Diagnostic Society was founded in 1816 and subsequently absorbed the Dialectic Society established in 1787 from which it takes its foundation date.[1] It claims to be the oldest society in Edinburgh and also the oldest debating society in Great Britain.[2] The Society traditionally meets on alternate Thursday evenings for public debates. Each meeting is lit by candlelight and attendees wear their individual National Dress or black tie.[3] Meetings consist of “the prosecution of literary and philosophical composition, criticism, and debate".[4]
-----Apart from its younger cousin, the Cambridge Union, the Diagnostics Society of Edinburgh is the only student society to have been granted an official coat of arms.