The “tribes” of AI

A few years ago, I attended a presentation by Pedro Domingos who was promoting his book – The Master Algorithm. In his book, he discusses the generalization of various AI approaches in pursuit of a “master algorithm” that (in theory) does everything well. He uses the term AI tribes to describe the different schools of philosophical and/or methodological approaches, each has its own focus, assumptions, and techniques for solving AI problems. I find these “tribes” to be very useful in discussing high-level AI concepts with non-specialists.

The tribes are (and yes, ChatGPT assisted with the generation of this list and the summarizing table):

Symbolists

• Focus: Logic and reasoning.
• Key Assumptions: Intelligence arises from rule-based manipulation of symbols.
• Approach: Based on formal logic, knowledge representation, and reasoning. Symbolists design systems that encode explicit rules and relationships.
• Techniques:
  • Expert systems.
  • Decision trees.
  • Logic programming.
• Strengths:
  • Excellent for tasks that require structured reasoning (e.g., legal or medical diagnosis).
  • Transparency: Rules are interpretable and explainable.
• Challenges:
  • Struggles with tasks involving unstructured or noisy data.
  • Limited ability to learn rules autonomously.
• Representative Algorithm: Decision trees (e.g., ID3).

Connectionists

• Focus: Neural networks and learning from data.
• Key Assumptions: Intelligence emerges from the interaction of simple computational units (neurons).
• Approach: Inspired by the brain, connectionists use neural networks to model learning processes.
• Techniques:
  • Deep learning (e.g., convolutional and recurrent neural networks).
  • Perceptrons.
• Strengths:
  • Handles large, unstructured data (e.g., images, audio, text).
  • Learns patterns and representations autonomously.
• Challenges:
  • Lack of interpretability (“black-box” problem).
  • Requires large amounts of data and computational power.
• Representative Algorithm: Backpropagation in deep neural networks.

Evolutionaries

• Focus: Evolution and optimization.
• Key Assumptions: Intelligence can evolve through natural selection mechanisms like genetic variation and survival of the fittest.
• Approach: Uses evolutionary algorithms to optimize solutions over time.
• Techniques:
  • Genetic algorithms.
  • Genetic programming.
  • Evolutionary strategies.
• Strengths:
  • Good at optimization problems and finding novel solutions.
  • Effective for problems without clear gradients or structure.
• Challenges:
  • Computationally expensive.
  • Slow convergence compared to other methods.
• Representative Algorithm: Genetic algorithms.

Bayesians

• Focus: Probabilistic reasoning and uncertainty.
• Key Assumptions: Intelligence involves reasoning under uncertainty using probability.
• Approach: Models the world probabilistically and updates beliefs as new evidence becomes available.
• Techniques:
  • Bayesian networks.
  • Markov models.
  • Probabilistic graphical models.
• Strengths:
  • Handles uncertainty well.
  • Flexible in integrating prior knowledge and data.
• Challenges:
  • Computationally intensive for complex models.
  • Sensitive to the quality of prior assumptions.
• Representative Algorithm: Naive Bayes classifier.

Analogizers

• Focus: Learning by analogy.
• Key Assumptions: Intelligence is the ability to identify similarities and generalize from known cases.
• Approach: Relies on comparing new problems to past examples to infer solutions.
• Techniques:
  • K-Nearest Neighbors (KNN).
  • Support Vector Machines (SVMs).
  • Case-based reasoning.
• Strengths:
  • Works well with limited data.
  • Can solve problems without explicitly learning rules or parameters.
• Challenges:
  • Struggles with large datasets.
  • Computationally expensive at query time.
• Representative Algorithm: K-Nearest Neighbors.

Unifying the Tribes: The “Master Algorithm”

Domingos argues that the ultimate goal of AI research is to develop a Master Algorithm—a unified framework that combines the strengths of all these tribes. Each tribe brings unique insights and methodologies that, together, could lead to breakthroughs in achieving artificial general intelligence (AGI).

Tribe summaries

AI Tribe	Focus	Key Assumptions	Strengths	Challenges	Example Application
Symbolists	Logic and reasoning	Intelligence arises from rule-based manipulation of symbols	Excellent for structured reasoning; interpretable and explainable	Struggles with unstructured or noisy data; limited autonomous learning	Expert systems for medical diagnosis
Connectionists	Neural networks and learning from data	Intelligence emerges from simple computational units (neurons)	Handles unstructured data; learns patterns autonomously	Lack of interpretability (“black-box” problem); data and computationally intensive	Image recognition (e.g., facial recognition)
Evolutionaries	Evolution and optimization	Intelligence can evolve through natural selection	Good for optimization problems; finds novel solutions	Computationally expensive; slow convergence	Automated design (e.g., optimizing aircraft parts)
Bayesians	Probabilistic reasoning	Intelligence involves reasoning under uncertainty	Handles uncertainty well; integrates prior knowledge and data	Computationally intensive for complex models; sensitive to prior assumptions	Spam email filtering
Analogizers	Learning by analogy	Intelligence is identifying similarities and generalizing from examples	Works well with limited data; solves problems without explicit rules	Struggles with large datasets; computationally expensive at query time	Recommender systems (e.g., product suggestions)