Lindy’s Delicatessen, 51st & Broadway, NYC (credit: Bertil Carlson, via Wikimedia Commons)

Yes. The Cravath System. The case method.  And much more.

Here’s the technical definition of the “Lindy effect“: The robustness of an idea or technology (anything nonperishable) is proportional to its longevity.

This post examines how we can observe the Lindy effect in many facets of life, including law.  Some of these are obvious, like the Cravath System and the Langdellian case method, which are both in their second century and show no signs of fading.  But are there durable aspects of life and business we are overlooking because, rather foolishly, we’re favoring what is novel, shiny, and hyped?

Some very sophisticated thinkers argue Lindy is a mental model that causes us to focus on what matters, thus reducing systemic risk. Likewise, focusing power is a feature of statistics.  In this essay, I show the value of using data analytics to help us calibrate our beliefs about what’s Lindy in law.

Before diving in, however, it’s worth sharing the origins of the Lindy effect.

Lindy’s delicatessen

The origins of the Lindy effect trace back to the early 1960s, when a group of comedians and talent scouts gathered each night at Lindy’s delicatessen in New York to discuss the vagaries of show business. Through raucous debate, they concluded the life expectancy of a television comedian is directly proportional to the comedian’s total exposure to the medium. Thus, following “Lindy’s Law”:

If … [a comedian] undertakes a regular weekly or even monthly program, his chances of survival beyond the first season are slight [as he will exhaust the finite supply of his material] … [B]ut if he adopts the conservation of resources policy favored by these senescent philosophers of “the Business,” and confines himself to “specials” and”guest shots,” he may last to the age of Ed Wynn [a peer of remarkable longevity].

See Albert Goldman, “Lindy’s Law,” The New Republic, June 13, 1964.

Roughly twenty years later, a serious polymath named Benoit Mandelbrot put Lindy’s Law into mathematical form and concluded the talent scouts got it wrong. The more television appearances a comedian makes, the more appearances they are likely to make in the future. See The Fractal Geometry of Nature at 342 (1982) (reformulating Lindy’s Law into a general principle on creative output).

As part of his broader theory on antifragility, the statistician and essayist Nassim Taleb recently refined Mandelbrot’s findings and dubbed his formulation the Lindy effect. Taleb writes:

If a book has been in print for forty years, I can expect it to be in print for another forty years. But … if it survives another decade, then it will be expected to be in print another fifty years. This, simply, as a rule, tells you why things that have been around for a long time are not “aging” like persons, but “aging” in reverse. Every year that passes without extinction doubles the additional life expectancy. This is an indicator of some robustness. The robustness of an item is proportional to its life!

Taleb, Antifragile: Things That Gain from Disorder at 318 (2012). In a 2017 essay, Taleb  elaborated on the Lindy effect, noting that “[t]he only effective judge of things is time.” Taleb, “An Expert Called Lindy,” Incerto, Jan. 9, 2017.

According to Taleb’s formulation, people can’t be “Lindy,” but their life’s work and legacy can be.  Also, bad things can be Lindy, such as exploitation, sexism, and racism.

The Lindy playbook

In 2020, I was very worried about the rise of troubling and incendiary events in the United States—pandemic, conspiracy, inequality, racism, protest, death. Reflecting on who seemed best able to make sense of it, historians and lawyers feature prominently in my mind. In their own ways, observers like Heather Cox Richardson (historian) and Berry Berke (lawyer) focused our attention on durable factors, both the helpful and the destructive.  Their tools of the trade, for the most part, are words and narrative.  They are trying to distill down complex events into a few themes or “drivers” that really matter.

Paul Skallas, aka LindyMan

More recently, I became familiar with some of the commentary of Paul Skallas, a tech lawyer and writer, who mines the lessons of history, routinely stretching back into antiquity, for practical and enduring lessons that the rest of us are missing. See Ezra Marcus, “The Lindy Way of Living,” NY Times, June 17, 2021. Inspired by Taleb, Skallas has turned Lindy into a lifestyle, which he shares with the world via his Lindy Newsletter on Substack, his podcast, “Lindy Talk,” and Twitter (@PaulSkallas aka LindyMan). Topics include diet, exercise, health, dating, and pretty much everything else.

The June 2021 Times article quotes Skallas, “Lindy exists chiefly for your protection, for risk/survival strategies in the modern world.” Without a Lindy perspective, we’re easy prey for “new products, new academic disciplines, new books, new technologies, new foods, new living arrangements, new ‘theories’ on life, new postures.” Instead, Skallas is looking for practices with a basis in antiquity. See Id (providing intermittent fasting and a vegan/pescetarian diet as examples).

It is very interesting that Skallas is a lawyer. In my experience, the natural skepticism of lawyers can poke holes in virtually anything—except, perhaps, what’s constant and durable based on the passage of time.

Lindy in law

Naturally, I started ruminating on what is likely Lindy in law. For many years, I have built and maintained a large-scale model of law firm profitability that draws upon ALM data as well as several other sources.  See, e.g., Post 238, Post 074. The model now includes 20 years’ worth of annual results, which is enough data to begin the hunt for truly durable predictors.

Figure 1 below presents a relatively simple and intuitive example, which is the relationship between leverage (ratio of non-partner lawyers to partners) and average partner compensation.

Leverage’s connection to profit has withstood twenty years’ worth of market forces, never dropping into insignificant territory (the orange baseline) and often differentiating high vs. low leverage firms at a $1,000,000 or higher premium. The large and consistent distance between each plot and the orange line suggests that leverage is Lindy, at least if the goal is higher profits.

When I want to explain how to use statistics to uncover the Lindy effect, the leverage example is a good one because it enables me to explain the methodology, as lawyers are unlikely to contest the underlying claim that leverage matters to profit.

To generate Figure 1, I used 21 separate regressions to predict average partner compensation in the AmLaw 200, one for each fiscal year, 2000 to 2020. Then, I compared how predicted profit differed between firms with high vs. low leverage, and all else equal. This difference reflects the importance of leverage for profit across time.

The statistician Andrew Gelman calls this comparison method the “secret weapon” for its ability to show trends while not falling victim to statistical complications inherent to studying patterns across time. This secret weapon is an ideal way to assess whether some factor’s importance is durable and worthy of focusing on strategically, i.e. Lindy.

Thus, let’s now turn to things that are less obvious, and arguably more important, than law firm leverage.

Three non-obvious Lindy examples in law

As an initial cut, I offer three factors with Lindy support: (1) willpower, (2) identity, (3) and relationships.

1) Willpower

Paul Skallas uses willpower to illustrate Lindy thinking. In the 1990s, the social psychologist Roy Baumeister developed a theory of “ego depletion” that gained widespread support. If you expend energy to decline donuts for breakfast, it’s harder to decline steak for dinner because you’ve depleted your reserve. But it turns out this idea isn’t Lindy, and most of Baumeister’s work failed to replicate. See Nir Ayal, “Have We Been Thinking About Willpower the Wrong Way for 30 Years?,” Harv Bus Rev, Nov. 23, 2016.

Instead, willpower looks more like what the ancient stoics described: a force that grows stronger through frequent activation. This is why willpower is Lindy, according to Skallas—thousands of years later we still read and talk about Seneca. See Paul Skallas, “Basic Concepts (Lindy),” Lindy Newsletter, July 27, 2027,

Lindy thinking means we observe a general durable behavior and make it situational. How about applying willpower to work-life balance? Leaving the office daily at five is easy enough. But some lawyers work longer, much longer. Determined and driven, they actively will themselves to put in the time, and their willpower grows stronger, perhaps with the goal of doing something difficult with long-term rewards.

So, here’s a Lindy explanation for what Henderson and Zorn found in their study of “A-Player” and “C-Player” large firm associates.  As reflected in the table below, which is based on more than 48,000 associate survey responses spanning eight years, A-Players (defined as associates in high internal demand by partners) were far more satisfied with their jobs, with job satisfaction being one of the largest sources of A-Player vs. C-Player difference.

See William Henderson & Chris Zorn, “Evidence-Based Strategies for Retaining High-Performing Midlevel Associates,” ALM Talent Management White Paper, July 2012, tbl. 6.

But where was the greater imbalance? Despite registering the same views of the firm’s family-friendliness, the A-Players were working 635 more hours than C-Players annually (after adjusting for firm, practice area, geographic market, and firm).  Further, they were thriving in this environment, reporting a much higher likelihood of remaining at the firm for the next two years.

Liisa Thomas

A Lindy view sees the A-Players exercising and strengthening their willpower and thriving.  I recently had a conversation with Liisa Thomas, a partner at Sheppard Mullin, who is studying how living a calling can explain lawyers’ capacity for business generation, among other things. Perhaps these high-demand associates have turned their work into a calling, finding meaning and value in the long hours and ostensible lack of work-life balance.

2) Identity

A statistical result is Lindy when we find support for it time and again. Now let’s consider the role for identity.

This is an immensely important Lindy factor given the profession’s emphasis on increasing diversity. In the full analysis that produced Figure 1, I included six substantively interesting factors, along with statistical adjustments for market headquarters location. One such factor measures the representation of lawyers from diverse racial/ethnic backgrounds in percentage terms.

There’s a strong link between racial/ethnic diversity and professional/social identity. Does identity in the form of race/ethnic diversity deliver (1) durable results and (2) in the preferred direction? The results are in Figure 2.

[click on to enlarge]
As reported in Post 238, the upper left panel shows the durability of a diversity dividend. Firms with a higher share of diverse ethnicity attorneys are more profitable in every year.

As my co-author Yvonne Nath uncovered, there is empirical support that viewpoint diversity results in decision-making. Abraham Lincoln required diverse viewpoints in his famous “Team of Rivals” Administration, and you can find similar arguments in Aristotle. See Scott Page, The Diversity Bonus: How Great Teams Pay Off in the Knowledge Economy (2017). Yet, what the above left panel suggests is that diversity’s impact of profitability is Lindy.

As an aside, Figure 2 shows how analytics give insight on durability for many factors. Growing your firm outside the United States (row three, left column) is a non-zero Lindy effect, but the evidence is problematic—the global strategy coincides with consistently lower profits. On the other hand, concentrating your lawyers in one or a few offices (having high “geographic concentration,” row two left column), looks Lindy. This configuration corresponds to gains of $500K to $800K from 2000 to 2020.

In other, more nefarious ways, identity conditions law through its effects on opportunity. Prestige and status concerns have long dominated large law firm hiring. This system reinforces practices that disadvantage underrepresented groups, especially Black lawyers. See Parker, “Advancing Black Lawyers,” LVN Insider, Jan. 2021.

Applying Lindy thinking, we understand how some exclusionary practices in law are anchored by identity. And sometimes, these practices end up creating business opportunities.

Consider the history about how Skadden, Arps, Slate, Meagher & Flom, and other Jewish law firms, came to dominate M&A and Litigation practices. See Wald, Eli, “The Rise and Fall of the WASP and Jewish Law Firms,” 60 Stan. L. Rev., 1983 (2010). As Wald explains, in 1945, most law schools dropped quotas and made it easier for Jewish students to enroll. More Jewish lawyers were now being trained in the Cravath System, and qualified to work in large legal markets like New York. Discriminatory hiring in the Wall St. WASP firms, however, along with the unwillingness of WASP firms to promote Jewish lawyers to partner left an abundance of exceptionally talented lawyers available. The WASP firms also eschewed what was less prestigious work, like proxy fights, hostile takeovers, and related litigation.

Joseph Flom saw this confluence of factors as an opportunity; the rest is history. I’m hopeful that Black lawyers who are excluded today can identify and profit from similar opportunities. With engagement and passion, the calling in place, brainstorm how discrimination and other identity factors have led prestige- and status-conscious lawyers to ignore business opportunities. (Black Venture Capital? Contracts for NCAA athletes now freed to profit from their likeness?)

3) Relationships

A third Lindy factor is the professional relationship, itself a function of other durable features of human connections.

For me, an early understanding of how much relationships matter in law came from work with the Law School Survey of Student Engagement (LSSSE). We were using LSSSE’s data to understand, from a list of 70+ factors related to law student experiences, which matter the most to students. Why are students satisfied with their legal education? I’ll add today, which of these factors has durability, at least as much as we can see across LSSSE’s 2009 to 2020 data history?

Focused on how the importance of various factors matters across time, Figure 3 examines nine, including three aspects of relationships.

[click on to enlarge]
As with the earlier “secret weapon” work, this data lets us see how strongly different factors distinguish students who were “Very Satisfied” with their entire law school experience. The longer a dot stays above the orange line, and at a high value, the more evidence this facet of students’ experience has durability. Note the full regressions for the 2009 to 2020 period include upward of 70 different factors; here I’m displaying a selected list of items legal education leaders should know about.

Scan across the nine panels and you’ll see mixed patterns. In terms of durability, however, nothing has quite the differentiating power of high-quality relationships with faculty (row two, middle) and especially students (row two, right panel.

In these cases, students who reported having high-quality relationships were significantly more likely to be satisfied with their entire law school experience over the full twelve-year period. Seeing this result persist across survey years (LSSSE involves different law schools in different years), and despite wild swings in context, indicates these relationships are foundational to an excellent law school experience.

Law school deans will have difficulty refuting these trends. There’s a reason to move some budget over from computing technology (row 3, middle panel = not Lindy) to social events, where relationships can be forged and strengthened. A harder organizational challenge than renewing software contracts, to be sure, yet with effects likely to matter long into the future.

Figure 3 also shows the lasting importance of how students’ perception that the “school provides support to succeed” (row 3, right panel = Lindy), the effect on satisfaction is large and durable.  As a measure of one’s sense of belonging, the item seems to tap directly into a school-based identity (Lindy).

Is it Lindy?

Asking, “Is it Lindy?” has transformed how I think about complex problems. This includes analysis of systems for law firm business and talent. In today’s information-rich environment, it’s easy to pay attention to novel, shiny, hyped-up ideas because they’re everywhere. For your benefit, it’s worth remembering ideas achieve Lindy status by withstanding the distortions of time—they are powerful. The longer they’ve been with us, the longer they’ll be here.

Lest we forget, Paul Skallas, who is making hay as the LindyMan, spends his days reading contracts. I’m convinced there’s something deeper connecting the proven skepticism imbued in lawyer training to the simple yet powerful elegance of the Lindy effect. So, why don’t we see more discussion about focusing on durable effects?

For one thing, the existence of Lindy phenomena is often evaluated through narratives, and thus not easily substantiated. My aim in linking Lindy thinking with statistics is to show how these two mental models are complementary. With proper methods and sufficient data, Lindy ideas confront the burden of evidence. This is the key to calibrating our beliefs using analytics. See Parker, “How to Get Value From Data Analytics,” Forum Magazine, Spring 2021. Now, when’s the next partner meeting to discuss increasing the firm’s leverage?

Second, Lindy factors strike at the heart of human connections. As such, building and enhancing these factors requires seriousness and systems. You have to do the work, and I know some firms are pulling this off.

Take the challenge of leadership communication, a key part of sustaining identity connections and relationships, yet an area where many firms fall flat. I have hard evidence one firm did great at communicating with its lawyers and professionals during the pandemic based on survey data. But this wasn’t a fluke—they’d been putting in the work for years. Every week ongoing several years, the firm held optional 2pm meetings for a conversation led by the firm’s Chairman and Managing Partner.

I can’t wait to tell him his communication strategy is Lindy.