Part of a series which began with Fake news and the ethics of belief.
’Cleave’ is an English verb with two virtually opposite meanings.
To ’cleave’ can mean to split or divide. Hence ‘cleaver’, which is a heavy knife for chopping meat.
But to ’cleave’ can also mean to cling or adhere, as in Genesis 2:24:

Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh.
Remember this as we dig deeper into Clifford’s move from ‘is’ to ‘ought’.
Clifford says we can ‘verify by direct observation’ that the instinct to ‘do good to man’ is ‘founded upon and agrees fully with’ the instinct to ‘do right’. Because of this, he says, we know by ‘immediate personal experience’ that ‘it is right to be beneficent’.1
I am assuming here that to ‘do right’ is by definition to do what you (morally) ought to do – that it would make no sense to question whether you (morally) ought to ‘do right’. I would go along with this.
But I am also assuming that Clifford is not saying that to ‘do good to man’ is by definition to do what you (morally) ought to do. This I would also agree with. We could for example imagine a religious fundamentalist deciding that what she (morally) ought to do was to obey her God, and that she should only ‘do good to man’ if that was what her God commanded.
After all, if it was true by definition that to ‘do good to man’ was what we morally ought to do, then this would not be something we could ‘verify by direct observation’. You cannot ‘verify by direct observation’ that all bachelors are unmarried. You can only know this by knowing what the words mean.
I am therefore taking Clifford to intend that doing ‘good to man’ or being ‘beneficent’ to other people is a matter of behaving in such a way that benefits others, perhaps by increasing their net happiness. And that because the link between beneficence and doing the right thing is something we can ‘verify by direct observation’, being beneficent is not by definition the right thing to do. Being beneficent is therefore not by definition how we ought to behave.
If I say ‘he is beneficent’ or ‘she does good to other people’ I am talking about what is the case, not about what ought to be the case. But if I say ‘X is the right thing for him to do’ I am talking about what he ought to do, and therefore what ought to be the case, rather than what is the case.
The two things which Clifford wants to cleave together are therefore starting out as things which Hume’s guillotine would cleave apart.
References
1 William Clifford (1877, 1879), ‘The Ethics of Belief’, in Lectures and Essays, Volume II, London: MacMillan and Co, p201.
© Chris Lawrence 2021
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