Sebastião José de Carvalho e Melo, the Secretary of State for Foreign Affairs and War at the time, was in attendance and surprised by the young man's erudition.

[3] After the 1755 Lisbon earthquake, when Sebastião José de Carvalho e Melo started to consolidate his power over the government, he was invited to act as the minister's particular clerk and protégé.

On 30 April, two magistrates and a cavalry force arrested him in his house in Tondela, and he was imprisoned in the Fort of Saint John the Baptist of Foz [pt], in Porto.

On October, he was sent to exile in Brazil (Ilha das Cobras, in Rio de Janeiro), and then to Angola (Fortress of Pungo-Andongo [pt]) without trial or hearing.

In 1788, after the death of two important government ministers, the 3rd Marquis of Angeja and of Aires de Sá e Melo, the Queen had Seabra da Silva head a new cabinet.