If the Outcome Isn't Up to You, Why Try?
A person who takes care of a sick relative cannot guarantee recovery. The uncertainty does not make the care pointless.
Epictetus addresses this problem directly. In Discourses 2.5, he distinguishes the external circumstances we encounter from the use we make of them. Circumstances are indifferent in the Stoic classification of good and evil. Our use of them calls for care, judgment, and responsibility.
He illustrates the distinction with games. A player does not control the throw of the dice, but must understand how to play the throw received. Uncertainty about the material does not excuse careless play. Discourses 2.5
For Epictetus, the ethical question concerns how we act with what is available. Simply putting in effort is not enough. Effort can serve an unjust purpose as readily as a just one.
Consider a modern example: applying for a position.
You have reasons to consider the pay, the work, your abilities, and the effect on people who depend on you. You can investigate the employer and prepare an honest application. You can also decide what you would be unwilling to say or do to obtain the position.
The employer’s decision remains uncertain. That uncertainty belongs in your deliberation from the beginning.
Acting with reservation means undertaking an appropriate action while acknowledging that its external completion may be prevented. You pursue the position without making its acquisition the condition of acting honestly.
This also explains why Epictetus’s teaching is social. He asks people to consider their responsibilities as members of a larger whole. An outcome being beyond your command does not remove the question of what you owe another person. Discourses 2.10
If uncertainty has become your reason for doing nothing, examine the proposed action itself. Is it reasonable? Is it fair? Does it serve a responsibility you actually have? What would count as pursuing it well?
You may have sufficient reason to act without having any assurance that you will succeed.