When Sugden rather abruptly informed his pupils in 1816 that he was concentrating on chancery work, Senior took steps to qualify as a Certified Conveyancer, which he did in 1817.

Senior became a good friend of Alexis de Tocqueville (1805–1859) whom he met in 1833 for the first time before the publishing of Democracy in America.

[8][9] Senior accompanied Lind and Harriet Grote to Paris (amid civil strife and a cholera epidemic).

It was backed by Richard Whately and others of the Oriel Noetics, and with the help of Thomas Mayo, he found an editor in Joseph Blanco White.

Early contributions from John Henry Newman, Edwin Chadwick and Senior himself (on the Waverley novels and William Jacob's views) were not enough to establish it, and it ceased publication in mid-1829.

[14] His writings on economic theory consisted of an article in the Encyclopædia Metropolitana, afterwards separately published as An Outline of the Science of Political Economy (1836), and his lectures delivered at Oxford.

Of the latter, the following were printed: Several of his lectures were translated into French by M. Arrivabne under the title of Principes Fondamentaux d'Economie Politique (1835).

In 1859 appeared his Journal kept in Turkey and Greece in the Autumn of 1857 and the Beginning of 1858; and the following were edited after his death by his daughter: Senior's tracts on practical politics, though the theses they supported were sometimes questionable, were ably written and are still worth reading but cannot be said to be of much permanent interest.

Senior regarded political economy as a deductive science, of inferences from four elementary propositions, which are not assumptions but facts.

What Senior failed to realize is that the turnover of capital stock depends on the length of the working day; he assumed it constant.

"If, giving credence to the out-cries of the manufacturers, he believed that the workmen spend the best part of the day in the production, i.e., the reproduction or replacement of the value of the buildings, machinery, cotton, coal, &c.," Marx writes, "then his analysis was superfluous.

In his letter[22] of 8 January 1836 to Lord Howick, Senior wrote, With respect to the ejected tenantry, the stories that are told make one's blood boil.

Senior's notes of his visits to Birr, County Offaly in the 1850s mention his surprise and concern that the everyday lifestyle of the Irish poor had changed so little, despite the famine disaster.