The tech tree from early access builds Techs (short for "technologies") are empire upgrades that cost science and provide various benefits and make additional techs and some laws and events available.
Tier 1 (80 Science)
Technology
Prerequisites
Effects
Ironworking
None
Stonecutting
None
Trapping
None
Divination
None
Administration
None
Tier 2 (120 Science)
Technology
Prerequisites
Effects
Labor Force
Ironworking
Husbandry
Ironworking
Drama
Stonecutting
Polis
Stonecutting, Trapping
Military Drill
Trapping
Aristocracy
Divination
Rhetoric
Administration
200
Tier 3 (200 Science)
Technology
Prerequisites
Effects
Navigation
Labor Force
Phalanx
Labor Force
Spoked Wheel
Husbandry
Forestry
Polis
Steel
Military Drill, Ironworking
Sovereignty
Aristocracy, Rhetoric
Metaphysics
Rhetoric
Tier 4 (400 Science)
Technology
Prerequisites
Effects
Coinage
Navigation
Citizenship
Phalanx
Portcullis
Drama
Land Consolidation
Forestry
Composite Bow
Rhetoric
Monasticism
Aristocracy
Machinery
Sovereignty
Tier 5 (600 Science)
Technology
Prerequisites
Effects
Scholarship
Citizenship
Stirrups
Spoked Wheel, Citizenship
Architecture
Portcullis
Manor
Land Consolidation, Composite Bow
Battleline
Steel, Phalanax
Doctrine
Monasticism
Torsion
Machinery
Cartography
Metaphysics, Navigation
Tier 6 (800 Science)
Technology
Prerequisites
Effects
Hydraulics
Coinage
Jurisprudence
Scholarship
Martial Code
Stirrups
Vaulting
Architecture
Bodkin Arrow
Manor
Cohorts
Battleline
Windlass
Torsion
Tier 7 (1000 Science)
Technology
Prerequisites
Effects
Lateen Sail
Hydraulics
Fiscal Policy
Jurisprudence
Barding
Steel, Martial Code
Infantry Square
Bodkin Arrow
Chain Drive
Windlass
Ballistics
Cartography
Tier 8 (1200 Science)
Technology
Prerequisites
Effects
Economic Reform
Lateen Sail, Fiscal Policy
Military Prestige
Barding, Infantry Square
Industrial Progress
Chain Drive, Ballistics
