Revenge of the Nerds

paulgraham.com

Technology

22 min read → 75 sec

Programming languages differ sharply in power, and that difference can decide software speed, team size, and competitive outcomes. Lisp is presented as a long-standing upper bound that mainstream languages have gradually approached.

Using the most powerful language available creates durable competitive advantage in software

Lisp's extra power matters most on hard, competitive problems

Programming languages are not equivalent, and some are better for certain problems

If languages were equivalent, there would have been no reason to replace C++ with Java

Mainstream languages in 2002 were still catching up to ideas Lisp had in 1958

Java, Perl, and Python form a sequence that becomes progressively more like Lisp

Lisp and Fortran began as separate trees, one from math and one from machine architecture

Lisp stayed relevant because it came from math, and math does not get stale

Lisp introduced nine ideas, and two remain distinctive: code as data and macros

Macros let programmers write programs that write programs, from abbreviations to whole new languages

More powerful languages produce shorter programs, and shorter programs take proportionally less time to write

ITA's 200,000 line Common Lisp fare search system beat Travelocity and Expedia by searching many orders of magnitude more possibilities

For product-sized projects with several hackers and at least six months of work, language power outweighs library convenience

Server-based software reduces pressure to use middle-of-the-road languages and enables newer ones

Managers often choose standard languages to avoid blame, even when that makes teams slower

Hiring is a weaker objection than managers think, because strong software teams should stay under ten people

Viaweb's Lisp choice worried some investors, but without Lisp it could not have built the product buyers wanted