Stoicism is the only philosophy that aims at increasing one’s mental strength. Its founders, Zeno of Citium (334-262 BC) and Cleanthes (330-230 BC) devoted more efforts to avoiding emotional misery than to achieving success and happiness.
Seneca followed the line of thought of his predecessors, but his recommendations are more subtle. It’s not hard to understand why: Seneca was more knowledgeable than the earlier Stoics.
Not only was he familiar with the ideas of Socrates (470-399 BC), Plato (427-347 BC) and Aristotle (384-322 BC), but he also possessed a wider experience of the world. None of his predecessors had occupied a high office in the Roman empire, nor acquired a large fortune.
Seneca’s Letters to Lucilius give remarkably modern advice on self-control (I would call it “mental strength.) I view the 5th Letter as particularly relevant in this respect.
Mental strength, Seneca affirms, is the result of self-reliance and moderation, not the cause; the purpose of cultivating virtue is to grow emotionally balanced, rational and highly resilient.
Seneca: the comparison to fishermen
I would compare Seneca’s ideal of a philosophically minded person to a fisherman, who lives modestly and self-sufficiently. Like a fisherman, the philosopher keeps going day after day, unaffected by fashions and social pressures.
The philosophically minded love human interaction, Seneca notes, but they will not be swayed by other people’s fear and preoccupations. They are also able to enjoy the pleasures of the world, but they will embrace moderation in order to preserve their peace of mind.
Seneca regards mental strength as the highest benefit from philosophy. Like other Stoic philosophers, he takes for granted that happiness is unlikely and adversity inevitable.
Everybody is confronted with adversity sooner or later. The purpose of philosophy is to develop mental and physical habits that render us practically immune to adversity. Mental strength is a synonym for emotional immunity to adversity.
Seneca: critique of luxury clothes
To explain the habits that contribute to mental strength, the 5th Letter to Lucilius gives the example of fine clothing. Seneca asks rhetorically, whether we should wear luxurious clothes if we can afford them.
Aristotle would have replied positively to this question. The purpose of having money is to enjoy it. If one can afford fine clothes, Aristotle would have considered self-evident that one should wear them and enjoy them. He would have rejected the Stoic call for moderation.
Seneca recommended the opposite course of action. Instead of wearing fine clothes, one should wear inexpensive ones and steer away from all luxury expenditures. No fine clothes, food, or travel. No criticising, gossiping or gambling.
Mental strength is the outcome of daily practice. If we steer away from luxury items, we won’t miss them in difficult times when they become unavailable or unaffordable. If we keep temptations at bay, they will not enslave us.
In the 5th Letter, Seneca exalts the principles of moderation and humility, which he regards as philosophical pillars. Even when it comes to the pursuit of knowledge, we should choose autonomous, quiet learning.
Would have Seneca condemned the pursuit of a prestigious degree or accreditation? Not necessarily. He would have asked about the student’s motivation. If the motivation is ethical, such as the wish to acquire advanced skills to practise a profession, he would not have opposed it.
Seneca: the virtue of detachment
Philosophical detachment is Seneca’s main recommendation for mental strength. It means not giving excessive importance to external circumstances. Whether we are criticised or praised, lionised or ostracised, we should remain calm.
Whether we are rich or poor, successful or unsuccessful, we should be content with little, Seneca recommends. Whether we can afford luxuries or not, we should lead a simple life and steer away from temptations.
Mental strength is the result of being “prepared to cope with adversity” and refusing to be “enslaved to desire.” Stoicism is condemning ambition because it increases the risk of suffering.
Seneca’s 13th and 24th Letters to Lucilius gives extra advice for maintaining one’s mental strength in the face of challenges. We can substantially reduce our worry, he notes, if we accept a potential failure before we engage in new friendships, romantic relationships, or business projects.
According to Seneca, everything we experience in life is temporary. It would be foolish to hold desperately to anything or anybody, instead of training ourselves in equanimity. Let us learn to accept losses with grace, and keep going day after day.
Seneca: the anticipation of adversity
Making backup plans is another method recommended by Seneca to enhance our mental strength. Let us call this method “mental preparation for disasters.” It consists of figuring out in advance what to do if we are hit by disaster A, B or C.
Even in the absence of feasible backup plans, we can draw important benefits from having thought about problems before they occur, and having assessed potential solutions or counter-measures.
Mental strength is an intellectual muscle that needs to be exercised every day. By thinking about potential disasters, we can train ourselves in maintaining our emotional balance when bad turns to worse. I can hardly imagine a most valuable skill in life. Let us apply ourselves to practising Seneca’s advice on this matter.
If you are interested in putting rational ideas into practice in all sorts of situations, I recommend my book “Undisrupted: How highly effective people deal with disruptions.”
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