[2] As a teenager, Tan often helped his father to translate his letters to overseas missionaries from Chinese to English.
He subsequently joined the private sector, serving as part of Kim Ching & Co's consulate in Thailand.
Tan also co-authored a book on Chinese expatriates in Singapore, titled Bright Celestials: The Chinaman at Home and Abroad (1894), with Lamont.
In 1898, together with Lim Boon Keng and Chinese scholar Khoo Seok Wan, Tan established the Chinese-language newspaper Thien Nan Shin Pao; he served as its general manager from 1898 to 1905.
[6] He became increasingly drawn to Buddhism and was a supporter of the Maha Bodhi Society founded by Sri Lankan revivalist Anagarika Dharmapala.