One day he attended a meeting of the Aryasamaj. The ideals of Aryasamaj were against caste systems and the several superstitions that prevailed at the time. Kesava Pillai enrolled as a member of Aryasamaj and changed his name to Kesava Dev. He also participated in the riot at Palghat, organized by the Aryasamaj and was nabbed by the police. Kesava Dev could not fully endorse the ideals of the Aryasamaj. He soon severed his connection and went to Trivandrum, where he met Kesari Balakrishna Pillai, Bhodeswaran and A.K.Pillai. Travancore at that time was agitating against the rule of the Regency. Kesava Dev had good intellectual company at Trivandrum and that helped him to mould his own strategy to tackle the vexing problems of the society. He has also involved in the freedom struggle, in his own way. He started writing articles and short stories in various periodicals like Sahodaran, Mahila Mandiram, Swarad, Swadesabhimani and Mathrubhumi. He also worked as a journalist in Malayalarajyam and Bhaje Bharatham. Kesava Dev never ceased reading. He had by now read Bernad Shaw, Romain Roland, Victor Hugo, Knut Hamsun, Maxim Gorkey, Leo Tolstoy and a number of others.

The wealth of knowledge acquired through extensive reading and the wisdom he gained through his interaction with the leaders in various fields helped him to excel not only as a writer but also as an orator. Dev never used to refuse an invitation to address a gathering. He travelled far and wide addressing meetings often out of his own money. It was during this time that Dev read about the Russian Revolution. He thought that he has received the answer for all the problems that the country faced. He even hoped that the second socialist revolution should take place in India. He declared himself a communist, a communist long before the party itself had any footing in Kerala. He prepared a book let on Russian Revolution named "Agniyum Spulingavum" (Fire and Spark) printed it and distributed personally. He took upon himself the responsibility of organising the coir workers in Alleppy into a Trade Union. He thus became the first person to initiate trade union movement in the State. But Kesava Dev would not stick to anything permanently. He could not digest the post-revolutionary changes in Russia. He not only ceased to be a communist but also began working against it. And for the same reason he vehemently opposed adoption of a politically coloured manifesto at the Progressive Literary Conference held at Trichur. Many tried to explain away Dev's attitude saying that he had a weakness to rebel against everything. But the fact remained that Dev rebelled because he had the courage of conviction to do so.