If "say implies do" - if the beliefs that you profess are constrained by consistency with the behaviors you enact - then doesn't that severely limit the scope of philosophical speculation?
Indeed it does. That's a feature, not a bug.
As I've explored before, many people conceive philosophy as a way of life to work like this: some great thinker initiates a school of thought, then its adherents identify with those ideas so strongly that they do whatever they must to put them into practice. It's a one-way street from leader to followers.
Although that model can help the adherents learn from the wisdom of the founder, it can also lead to all sorts of distortions if the adherents take that wisdom for certainty; a prime example is personal suppression of thoughts and behaviors that are not completely consistent with the original theory. Consider, for example, the very human phenomenon of grief. The ancient Stoics discouraged grieving, even going so far as to assert that you don't grieve over a broken cup, so why do you grieve over the loss of a spouse or child? Although that position is, to my mind, literally inhuman, an adherent of Stoicism might feel guilty about not living up to it.
Better, I think, to make sure that traffic on the street also flows in the other direction, so that you assent to a principle only if it arises from within your existing practice. This leads to a healthy sort of philosophical parsimony, a wisdom that is aligned with life as you live it. This approach to philosophy is almost scientific in its austerity, since theory must always align with the evidence of life.
Even better is a two-way street, in which wisdom and practice exist in a mutually reinforcing dialectic of continual learning and self-improvement. In my experience, this works best if I open myself to insights from many different schools of thought, since most of them have grasped some but not all of the truth in human affairs. By deeply encountering various thinkers and judiciously attempting to put their ideas into practice, I determine for myself whether I will accept their insights as part of my chosen wisdom.
In Book X of the Nicomachean Ethics, Aristotle makes two statements that comport with this dialectical vision:
True arguments seem most useful, not only with a view to knowledge, but with a view to life also; for since they harmonize with the facts they are believed, and so they stimulate those who understand them to live according to them.
And:
The truth in practical matters is discerned from the facts of life; for these are the decisive factor. We must therefore survey what we have already said, bringing it to the test of the facts of life, and if it harmonizes with the facts we must accept it, but if it clashes with them we must suppose it to be mere theory.
If more thinkers pursued this approach to the love and practice of wisdom, they would be more successful at threading a middle path and thus avoiding extreme opinions such as the Stoic position on grief. Although I don't expect that philosophical theorists will change their stripes, it's a policy that those who engage in the examined life can readily accept.
(Cross-posted at philosopher.coach.)
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