The name of Frank Ramsey is universally known amongst combinatorial mathematicians, but our casual mental picture of him can easily be an unimpressive one – the man who almost stumbled across the theorem that now bears his name, thereby anticipating Erdős and Szekeres, who of course gave the proper proof. Such an idea of Ramsey is entirely false: he was an absolutely brilliant man, who would certainly have become even more famous had he not died so young, and who would surely, it could easily be argued, have made yet further remarkable contributions to philosophy, economics and logic – and to combinatorics.