That Mr. McHenry attached a wider significance to Banneker's attainments than is implied in a merely personal achievement is shown in his statement that he considered "this negro as a fresh proof that the powers of the mind are disconnected with the color of the skin, or, in other words, a striking contradiction to Mr. Hume's doctrine, that the negroes are naturally inferior to the whites, and unsusceptible of attainments in arts and sciences?" "In every civilized country," said he, "we shall find thousands of whites, liberally educated and who have enjoyed greater opportunities for instruction than this negro, (who are) his inferiors in those intellectual acquirements and capacities that form the most characteristic features in the human race.[165] But the system that would assign to these degraded blacks _an origin different from the whites_, if it is not ready to be deserted by philosophers, must be relinquished as similar instances multiply; and that such must frequently happen, cannot be doubted, _should no check impede the progress of_ _humanity_, which, ameliorating the conditions of slavery, necessarily leads to its final extinction."[166] Referring to their attitude, the publishers said in their editorial notice that "they felt gratified in the opportunity of presenting to the public, through their press, an accurate Ephemeris for the year 1792, calculated by a sable descendant of Africa." They flatter themselves "that a philanthropic public, in this enlightened era, will be induced to give their patronage and support to this work, not only on account of its intrinsic merit (it having met the approbation of several of the most distinguished astronomers of America, particularly the celebrated Mr. Rittenhouse), but from similar motives to those which induced the editors to give this calculation the preference, the ardent desire of _drawing modest merit from obscurity_ and controverting the long established illiberal prejudice against the blacks."[167] Banneker had himself not lost sight of the probable effect of his work in reshaping to some extent the public estimate concerning the intellectual capacity of his race. And this was the thought that prompted him to send a manuscript copy of his first almanac to Thomas Jefferson, then Secretary of State in Washington's cabinet. In his letter to Jefferson, dated August 19, 1791, Banneker made, with characteristic modesty, a polite apology for the "liberty" he took in addressing one of such "distinguished and dignified station," and then proceeded to make a strong appeal for the exercise of a more liberal attitude towards his downtrodden race, using his own achievements as a proof that the "train of absurd and false ideas and opinions which so generally prevails with respect to the Negro should now be eradicated."[168]