You have run the numbers. You have the spreadsheet, the runway, the story you would tell people. What you do not have is certainty, because the question is not really financial. It is the Sunday-night feeling that has stopped going away, the sense that you are spending the only hours you get on something that has quietly stopped mattering.
Quit or stay is the wrong frame to start with. Three thinkers on the Consilium roster would each tell you that the decision you are agonizing over is downstream of a question you have not answered yet, and they would not agree on what that question is.
Seneca: the restlessness may travel with you
Seneca would slow you down before you do anything. He watched wealthy Romans flee their villas for the coast, convinced a change of place would fix a discontent that had nothing to do with place. His diagnosis was unsentimental: much of what you call the problem with your job is a judgment you are making about it, and judgments follow you. Change the office and the same person shows up to the new one.
This is not an argument for staying. Seneca left public life himself. It is an argument for knowing what is actually yours to control before you spend your leverage. If the misery is the commute, the manager, the specific rot of this one place, leaving is rational. If the misery is a lack of anything that would satisfy you, no resignation letter reaches it.
They lose the day in expectation of the night, and the night in fear of the dawn.
He would ask you to separate the two before you act: what about this is the situation, and what about this is you? Quit the situation freely. Do not expect quitting to quit the part that is you.
Thoreau: the job is the quiet desperation
Henry David Thoreau would take Seneca's caution and push against it. Yes, discontent can be internal. But he would say you should be suspicious of any philosophy that talks you into staying inside a machine that is grinding you down. He went to the woods precisely because he suspected that most people trade their one life for a security that never actually arrives, and call the trade maturity.
Thoreau would not be impressed by the spreadsheet. He would ask what the job is costing in the currency that does not show up on it: attention, mornings, the version of you that used to have ideas. To him the danger is not quitting rashly. The danger is postponing your life so long and so reasonably that you look up at the end and find you were never really in it.
The mass of men lead lives of quiet desperation.
He would want to know whether you are staying because it is right, or because leaving is frightening and staying is what everyone around you has agreed to call sensible.
Frankl: comfort was never the question
Viktor Frankl would refuse both of their framings, because both are still arguing about how the job feels. Frankl survived the camps and came out convinced that human beings can endure almost any how if they have a why. The right question, to him, is not whether the work makes you happy. It is whether it is in the service of something you would stand behind.
He would point out that a job which is hard, tedious, even joyless can still be worth doing if it is pointed at a meaning you have chosen, and a job which is pleasant and well paid can quietly hollow you out if it is pointed at nothing. Fulfillment, he argued, is a side effect of commitment to something beyond yourself, never a thing you obtain by chasing it directly.
Those who have a why to live can bear with almost any how.
So before you draft the letter, he would ask: what is this job for? Not what does it pay, what does it serve. If you cannot answer, quitting will not give you the answer, and neither will the next job.
Where they disagree
Seneca says look inward first. The restlessness might be a judgment you are carrying, and if it is, a new job just relocates it. Master the judgment before you spend the leverage.
Thoreau says look at the cage. Institutions are very good at persuading you that your dissatisfaction is a personal failing rather than a reasonable response to a life that is being slowly taken from you. Do not let good philosophy become an excuse for a bad situation.
Frankl says both of them are still measuring the wrong thing. Stop asking whether the work feels good and ask what it is in service of. Meaning, not comfort, is the axis the decision should turn on.
The tension is sharp. Thoreau would tell Seneca that "examine your judgments" is exactly the reasoning that keeps people at desks for thirty years. Seneca would tell Thoreau that walking out without self-knowledge just builds a new cage in a nicer location. Frankl would tell both that a person who leaves for freedom and a person who stays for security can be equally lost, because neither has said what any of it is for. None of them would tell you what to do.
The question you came here to avoid
You searched this because you want permission, either to go or to stay. But permission is not what is missing. What is missing is an honest account of what you are actually deciding between.
So here is the question underneath the question: if the money and the fear were both off the table, would you still be unsure, and if you would, is the real problem the job at all?