Joseph Priestley and the Slave Trade

William Wilberforce, architect of the Act that abolished the slave trade in the British Colonies

The Reverend Dr Joseph Priestley was a philosopher, theologian and scientist who was one of the most politically radical figures of the Unitarianism of his time, and a leading light in the culture of the 18 century Enlightenment.

In 1788 he delivered a sermon in Birmingham on the subject of the Slave Trade, using a wide range of arguments against the slave trade. Where many white opponents of slavery focused on the cruelty and abuses of slavery without seeing Africans as their equals, Priestley, who had studied many different cultures recognised the psychological, cultural and intellectual equality of all human beings whatever their colour.

In his sermon he wrote: "Man has the power of reflection in an eminent degree; and it is this that makes him miserable in a state of servitude. Through agony of mind, great numbers of Negroes put an end to their own lives…. and they will be incapable of any degree of happiness in a state of servitude, till their feelings are blunted, and they are reduced to a condition nearly approaching that of the brutes.
'Secondly, Africans were not culturally or intellectually inferior to Europeans: Some Europeans, finding Negro slaves in this wretched degraded condition, to which they themselves have reduced them, have had the assurance, and the folly, to pronounce them to be a species of men greatly inferior to themselves. But were the Europeans treated in the same manner a sufficient length of time, it is demonstrable that the most intelligent of them would be no better. Those who see Negroes in their native country, or in circumstances of better treatment among ourselves, are satisfied that they are by no means inferior to Europeans in point of understanding. According to the observations of a late ingenious traveller, the ancient Egyptians so famed for their wisdom, were the very same people with the present Negroes.'

Slavery was, he claimed, 'perhaps the greatest, and most crying evil under the sun'. Common humanity required action against it: 'You will consider all mankind as brethren, and neighbours…As men, and as Christians…we should not rest ourselves not only for our relations…or friends; not only for our countrymen; not only for Europeans, but for the different inhabitants of Asia, Africa or America; and not only for Christians but for Jews, Mahometans, and Infidels. And as we ought to feel for our fellow men we ought, to the utmost extent of our influence, to exert ourselves to relieve their distresses.'

Priestley argued that the slave trade was psychologically cruel: 'I have been informed by a person who resided in Jamaica, that it is usual for the slaves, after they are purchased, to shudder at the sight of a fire, or kitchen utensils, imagining that they are to be killed and eaten, till older slaves convince them that nothing of that kind is intended. What the poor creatures must suffer with this idea on their minds all the voyage, and the terror it must impress on the country in general, in which thousands who are never taken know they are liable to it, is not to be estimated, and for which no good treatment of slaves can compensate.'

Priestley argued that the slave trade was physically brutal: 'In order to raise our sugar, and other West-India commodities, perhaps half a million of persons are annually destroyed, and in a manner peculiarly shocking to humanity. To die by an earthquake, by pestilence, or even by famine, would be merciful compared with the manner in which these poor wretches often perish. All the European plantations taken together are said to require an annual supply of sixty thousand fresh slaves; but these are those that remain after so many have died in what is called the seasoning, before they can be brought to bear the labour to which they are made to submit; and after so many more have been lost during the voyage, owing to their mode of confinement, and ill usage on board, that it is said not less than a hundred thousand are annually exported from Africa. And some say that before this ten are destroyed for one that is secured, and safely lodged on board the ships.'

Priestley argued that Slavery was morally degrading, that slavery degraded women and destroyed families: 'The shocking indecencies to which the females are subjected during the voyage, and afterwards, and the cruel separation of the nearest relations and friends, husbands and wives, parents and children, both when they are put on board the ships, and at the place of sale, would be heard with horror by all but those who are habituated to this traffic.' It also dehumanised the owners of slaves. The power that masters wielded debased them morally: 'Such a power as that which a master exercises over a slave necessarily tends to make him haughty, cruel, and capricious, unfit for the society of his equals, which is the happiest state of man'.

Priestley argued that moral arguments were always more important than economic ones: 'Some say that if we abandon the slave trade we give up a valuable source of national profit, and yield it to our rivals. Should this be the case, still a Christian nation should not hesitate to do what is right in itself. A trade so circumstanced as this may justly be termed wicked, and unlawful, such as no advantage can justify.' He went on to argue that ending slavery could be economically beneficial: 'End the expensive plantation system and enable the African economies to develop with free labour. The Quaker masters who freed their chattels and employed them as paid labourers, found that they did more work as freemen than as slaves.'

Priestley argued that the Slave- Slave Owner Relationship was degrading to the humanity of all involved: 'In slavery human beings were subjected to the arbitrary will of others Under humane masters, slaves may, no doubt, enjoy a certain degree of happiness; but still they are slaves, subject to the wills, and consequently the caprices, of others; and there is no proper security from the greatest outrages, but in the protection of law. Slavery is an abuse of power: In general, it is said, that in our plantations slaves are employed so many hours every day, excepting Sundays, in the service of their masters, that they have only one for themselves, and but little sleep. For remissness in labour they are severely beaten, and for rebellion (as any attempt to recover their liberty is called) they are generally gibbeted alive.'

The English, Priestley suggested, were the worst slave masters: 'No Europeans whatever use their slaves with so much cruelty as the English. The Spanish have excellent regulations in their favour, in consequence of which the slaves can work out their own freedom; and the French government has also interposed by a code of laws enacted for this very purpose. But the slaves belonging to the English are almost wholly left to the mercy of their masters; and the annual consumption of them is itself proof of the most cruel usage.'

Priestley’s willingness to attack people in his own class and country undoubtedly contributed to his unpopularity which led to the ‘Priestley Riots’ in Birmingham in 1791.

Priestley said: 'I stand in need of liberty myself, and I wish that every creature of God may enjoy it equally with myself.'

Researched by the Reverend Tom McCReady

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