Logical reasoning (analytic or logical thought) is generally concerned with what is or is not true or false with some greater or lesser strength of (logical) conviction. It gives us principles for deciding what to believe and accept as knowledge as opposed to what not to believe and what to reject as knowledge.
Moral reasoning in particular is concerned with what is right or wrong, good or bad, here again with some greater or lesser strength of (ethical) conviction. It provides us with principles for choosing what to do and how to act and interact, as opposed to what to refrain from doing and how not to act and interact.
The challenge is that these two modes of reasoning, as it were, overlap – they intersect in obvious ways: e.g. ‘one ought to believe what is true and reject what is false,’ clearly qualifies as a moral judgment and ethical principle. At the same time, any decision to act or interact in one way or another should be justified by logical principles applied to moral assertions.
Example: one of Kant’s categorical imperatives is, “one must do only what one can will that all others should do under similar circumstances.” Categorical imperatives, for Kant at least, are unconditional moral laws that apply to all rational beings; they are independent of any personal motive or desire.
To illustrate the problem using Kant’s imperative, consider the current front runners for the upcoming election for the US presidency – Hillary Clinton v. Donald Trump. An argument for either candidate could be:
- One must do only what one can will that all others should do under similar circumstances.
- If I had my way (if my will prevailed), everyone should vote for candidate X.
- Therefore, by #1 and #2, I should vote for candidate X (and everyone else should too).
Observe that this argument is both logically and morally sound, regardless which candidate is substituted for X – the argument works equally well for either Clinton or Trump. Perhaps this is what’s referred to as ‘the will of the people’ being expressed at the polls. But the problem doesn’t end here.
Philosopher David Hume pointed out the ‘is/ought gap,’ namely, that any argument with an ‘ought’ conclusion must have at least one ‘ought’ premise. #1, #2, and #3 in the argument above are all ‘ought’ statements (‘should’ appears in all three), so this criterion is satisfied.
Hume’s major concern was the inherent distinction between what is, on one hand, vs. what ought to be, on the other. Not least of the problems caught up in this distinction is the simple fact that one may perfectly well believe and know what one ought to do, but at the end of the day, choose to do something entirely different. I may be strongly convinced and convicted that Clinton should be the next US President, yet walk right into the voting booth and cast my vote for Gary Johnson anyway.
[The logically fallacious and morally corrupt 2016 Presidential election is an entirely different matter, which I’ll soon be addressing on my blog, www.semiotic.com.]
I strongly believe with great conviction that one should not eat more calories than they burn up in a day, caloric intake should be far more nutritious than purely self-indulgent, and one should regularly exercise both vigorously and moderately. Given any opportunity, however, I will frequently choose dark chocolate over kale, espresso over green tea, and a movie on TV over swimming laps or taking a walk.
Am I therefore irrational or immoral – or both? Strictly speaking, yes: I’ve acted in a way that is logically inconsistent with my moral beliefs. When I eat the kale, drink the green tea, and swim laps or take a walk, I’m acting in a way that is logically consistent with my moral (‘I should ….’ or ‘I ought ….’) beliefs and ethical principles.
When I change the argument to allow exceptional violations or to generally justify actions that still conflict with underlying categorical imperatives (e.g. ‘one ought to maintain good health with a nutritious diet and regularly exercise’), this is called a rationalization.
The bottom line is that logical reasoning is the broad category. Moral reasoning is a mode or type of reasoning subsumed within that broader category. Moral reasoning is specifically concerned with claims and beliefs regarding what ought to be true, what ought to be done, etc., apart from what may or may not factually be the case.